SBG Series. Support Notes. Wireless N Fiber WAN Small Business Gateway. (Green Product) Version 1.00 Edition 1, 04/2014

Transcription

1 SBG Series Wireless N Fiber WAN Small Business Gateway (Green Product) Version 1.00 Edition 1, 04/2014 Support Notes Copyright 2014 ZyXEL Communications Corporation

2 Table of Contents Chapter Introduction... 3 Feature/Function Introduction... 3 Application Scenario Introduction... 3 Chapter Multi-WAN connectivity with load balancing and fail over... 4 Increased bandwidth and reach... 4 Robust security designs... 4 Secure business access via VPN... 5 Comprehensive management... 5 Chapter Scenario 1 VLAN... 6 Scenario 2 Firewall... 7 Scenario 3 User Access Control... 9 Scenario 4 3G backup Scenario 5 NAT Scenario 6 FullFeature NAT Scenario 7 Virtual Private Network (VPN) Scenario x Scenario 9 Maintenance Log Chapter Product FAQ: Wireless FAQ... 28

3 Chapter 1 Introduction The ZyXEL SBG (Small Business Gateway) Series is the Multi-WAN Gateway which provides high speed internet access for business users. It features not only VDSL2/ADSL2+ functionality, but also one GbE WAN with SFP interface (SBG3500-N Series only). This comprehensive device can flexibly offer Multi-WAN connectivity to adopt various Internet connection interfaces. Feature/Function Introduction VDSL/bonding + GbE/SFP (SBG3500-N) Multi-WAN connectivity with load balancing and failover Up to 20 concurrent VPN sessions 4*GbE LANs H/W Packet engines/ipsec engine External Captive Web Portal Metal case, Rack-Mountable, Front port Robust security designs Secure business access via VPN Comprehensive management Application Scenario Introduction Internet Access Wireless Access Firewall defense against Virtual Private Network (VPN) connection Virtual Local Area Network (VLAN) Maintenance Tool 3

4 Chapter 2 Multi-WAN connectivity with load balancing and fail-over The ZyXEL SBG Series provides multiple WAN interfaces including DSL, Gigabit Ethernet and 3G WAN backup to establish load balancing or backup WAN connectivity. Service providers can flexibly offer WAN services of the highest availability in one single box for small business owners to enjoy. Powered by the load balancing and fail-over mechanisms among multiple WANs, it maximizes WAN stability for mission-critical Internet applications with benefits from the integrated bandwidth. Increased bandwidth and reach The SBG3500-N supports ADSL2+/VDSL2 bonding and dual-personality Ethernet WAN functionalities that enable service providers to increase bandwidth and extend coverage. With the available copper lines, service providers can take advantage of ADSL2+/VDSL2 bonding to not only provide higher speeds for the existing subscribers, but also improve the reach to users faraway from central sites. If fiber lines are preferred, the SBG3500-N Series can use the Small Form Pluggable (SFP) interface to connect Fiber Ethernet that extend distance much longer with Gigabit-level performance, or simply connect to other Ethernet WAN devices. Robust security designs Based on Access Control List (ACL) rules, Stateful Packet Inspection (SPI), Denial of Service (DoS) and Distributed Denial of Service (DDoS) features, the ZyXEL SBG Series provides the first-line defense against hackers, network intruders and other harmful threats. The configurable Demilitarized Zone (DMZ) is another benefit that provides more flexible accessibility while preventing external attacks toward the confidential resources and databases. 4

5 Secure business access via VPN The ZyXEL SBG Series allow small businesses to establish stable Virtual Private Network (VPN) connections with partners as well as branch offices. Road warriors and telecommuters can use IPsec as well as L2TP or PPTP VPN to safely access corporate networks without maintaining VPN software on their PCs. The SBG Series is also designed with VPN HA features to ensure that the VPN connectivity is always on for the business needs. Comprehensive management The ZyXEL SBG Series offer a two-level login privilege mechanism to differentiate user segments; and the ISP can also define the policies for the limited account to easily manage them with the integrated profile database. It also provides TR-069 and Simple Network Management Protocol (SNMP) for service providers to conduct remote device management tasks. 5

6 Chapter 3 Scenario 1 VLAN 1.1 Application scenario Since security is an issue, the IT manager would like to move the server to a distinct broadcast domain called ServerGroup. General user cannot access the Server or capture the server packets even if they plug into same physical LAN. Besides, both LAN users and the server can still access the Internet without any issue. 1.2 Configuration Guide 1. Go to Network Setting> Interface Group/VLAN > Click on Add New Interface Group. 2. Enter the Group Name ServerGroup. 3. Enter the 802.1q number Enable the Port [LAN4] Member checkbox. 5. Click on Apply. 6

7 Scenario 2 Firewall 2.1 Application scenario SBG Series Firewall has the capability to limit only specific users from accessing the LAN Server. The others users access requests will be dropped or rejected. 2.2 Configuration Guide 1. Go to Security> Firewall > Access Control > Click on Add new ACL rule. 2. Add ACL rule for to allow specific users to access LAN RDP Server. 1. Enter the Filter Name ForRDP. 2. Select the Order Select direction from WAN to LAN. 4. Select Source Device Specific IP Address. 5. Enter Source IP address Select Destination Device Select IP Type IPv4. 8. Select Service RDP. 9. Select Policy ACCEPT. 10. Click on Apply. 3. Add ACL rule to drop untrusted users from accessing the LAN RDP Server. 1. Enter the Filter Name DropAny. 7

8 2. Select the Order Select direction from WAN to LAN. 4. Select Source Device Specific IP Address. 5. Keep Source IP address empty (It means Any). 6. Select Destination Device PC-1( ). 7. Select IP Type IPv4. 8. Select Service Specific Service. 9. Keep Protocol empty (means Any). 10. Select Policy Drop. 11. Click on Apply. 4. Go to Security> Firewall > General > Click Firewall Enable > Click on Apply. 8

9 Scenario 3 User Access Control 3.1 Application scenario The SBG Series User Access Control allows the IT manager to arrange Internet access scheduling to limit specific or all LAN PCs Internet access usage time. 3.2 Configuration Guide 1. Go to Security> User Access Control. 2. Add a new profile to control users. 1. Click Add new profile. 2. Check Active. 3. Enter User Access Control Name (ex: Team-Member). 4. Select Network User All. 5. Select working Day Monday, Tuesday, Wednesday, Thursday and Friday. 6. Arrange Time 07:00 till 18: Click on Apply. 8. Select User Access Control Enable. 9. Click on Apply. 9

10 Scenario 4 3G Backup 4.1 Application scenario 3G backup allows the SBG Series to keep the Internet connection when the primary WAN connection has failed. 4.2 Configuration Guide 1. Go to Network Setting> Broadband > 3G WAN. 2. Enter the Username/Password if the ISP requires it. 3. Enter the PIN code if SIM card PIN is enabled. 4. Enter the Dial string. 5. Enter the APN string or number. 6. Select Connection Nailed UP if you would like to make the dongle keep the connection. 10

11 7. Click on Apply. Scenario 5 NAT 5.1 Application scenario NAT provides system administrators with an easy solution to create a private IP network for security and IP management. Powered by NAT technology, the SBG Series supports complete NAT mapping and most popular Internet multimedia applications. This functionality is best demonstrated with the NAT port forwarding feature implemented in the CPE. In a scenario shown in the above diagram, we have an RDP server installed behind the SBG Series with an IP assigned by the local DHCP server ( ). How should we configure the SBG Series, so that the notebook at the WAN site can access the RDP server? The following step-by-step guide illustrates the setup procedure. 5.2 Configuration Guide Port Forwarding 1. Go to Network Setting> NAT > Port Forwarding. 2. Click on Add new rule. 3. Enable the Active checkbox. 4. Enter Service Name (ex: ForRDP). 5. Select current WAN Interface (ex: ADSL). 6. Enter Start Port Enter End Port Enter Translation Port Enter Translation Port Enter Server IP Address

12 11. Select Protocol TCP. 12. Click on Apply Applications 1. Go to Network Setting> NAT > Applications. 2. Click on Add new application. 3. Select current WAN Interface (ex: ADSL). 4. Enter Server IP Address Select Application Category Applications. 6. Select Application Forwarded Remote Desktop Connection. 7. Click on OK. Scenario 6 FullFeature NAT 6.1 Application scenario Another common question from customers is that they want to use multiple public IP addresses on prestige routers and would NAT them their internal IP addresses on one-to-one or many-to-one basis. This process is very simple and explained below. The scenario is Multiple Global IP addresses for clients and servers (One-to-One, Many-to-One, Server Set mapping types are used). 12

13 In this case, we have 2 IP addresses from an ISP via ADSL. We have a very busy internal FTP server and also LAN users. In this case, we want to assign the 2 IP addresses by the following way using 2 NAT rules. - Rule 1 (One-to-One type) to map the FTP Server with LAN-IP1 ( ) to WAN-IP1 ( ). - Rule 2 (Many-to-One type) to map the other clients ( ~ ) to WAN-IP2 ( ). 6.2 Configuration Guide Activate FullFeature NAT of a specific WAN interface 1. Go to Network Setting> Broadband > WAN Interface ADSL > Click on Edit. 2. Select NAT Enable. 3. Select FullFeature NAT Enable. 4. Select NatSet number (ex: 1). 5. Click on Apply. Remove FullFeature WAN interface from Multi-WAN rules 1. Go to Network Setting> Broadband > Multi-WAN >WAN Interface ADSL > Click on Delete. 2. Click on Yes. Configure NAT Address Mapping rule for Server 1. Select Type NAT One-to-One 2. Enter Local Start IP Enter Global Start IP Select Set number Click on OK. Configure NAT Address Mapping rule for General Users 1. Select Type NAT Many-to-One 2. Enter Local Start IP Enter Local End IP Enter Global Start IP

14 5. Select Set number Click on OK. Scenario 7 Virtual Private Network (VPN) 7.1 Application scenario VPN provides business users a highly secure path to transmit data. The following two scenarios describe the general usage of VPNs. - IPSec VPN (Site-to-Site): - L2TP VPN: 7.2 Configuration Guide IPSec VPN SBG1: Configure General information 1. Go to VPN > IPSec VPN > Setup. 2. Click on Add New Entry. 3. Check Enable. 4. Enter Connection Name (ex: VPNtoSBG2). 5. Enable the Nailed-up checkbox. 6. Enable the NAT Traversal (NAT-T) checkbox. 14

15 7. Select Application Scenario Site-to-Site. 8. Select My Address ADSL. 9. Enter Primary Peer Gateway Address Configure Authentication information 1. Select Key Exchange Mode Auto. 2. Select Pre-Shared Key and enter Configure Phase 1 1. Enter SA Life Time Select Negotiation Mode Main. 3. Select Encryption AES Select Authentication SHA1. 5. Select Key Group DH2. 6. Enable the Dead Peer Detection (DPD) checkbox. Configure Phase 2 1. Enter SA Life Time Select Tunnel Mode ESP. 3. Select Encapsulation Tunnel. 4. Select Encryption AES Select Authentication SHA1. 6. Enable Perfect Forward Secrecy (PFS) and select DH2. Configure Policy 1. Select Local IP Type Subnet. 2. Enter Local IP Address Enter Local Subnet Mask Select Remote IP Type Subnet. 5. Enter Remote IP Address Enter Remote Subnet Mask Click on Apply. SBG2: Configure General information 1. Go to VPN > IPSec VPN > Setup. 2. Click on Add New Entry. 3. Check Enable. 15

16 4. Enter Connection Name (ex: VPNtoSBG1). 5. Enable the Nailed-up checkbox. 6. Enable the NAT Traversal (NAT-T) checkbox. 7. Select Application Scenario Site-to-Site. 8. Select My Address ADSL. 9. Enter Primary Peer Gateway Address Configure Authentication information 1. Select Key Exchange Mode Auto. 2. Select Pre-Shared Key and enter Configure Phase 1 1. Enter SA Life Time Select Negotiation Mode Main. 3. Select Encryption AES Select Authentication SHA1. 5. Select Key Group DH2. 6. Enable the Dead Peer Detection (DPD) checkbox. Configure Phase 2 1. Enter SA Life Time Select Tunnel Mode ESP. 3. Select Encapsulation Tunnel. 4. Select Encryption AES Select Authentication SHA1. 6. Enable Perfect Forward Secrecy (PFS) and select DH2. Configure Policy 1. Select Local IP Type Subnet. 2. Enter Local IP Address Enter Local Subnet Mask Select Remote IP Type Subnet. 5. Enter Remote IP Address Enter Remote Subnet Mask Click on Apply L2TP/PPTP VPN Active L2TP VPN default rule 16

17 1. Go to VPN > IPSec VPN > Setup. 2. Click Default_L2TPVPN Edit. 3. Check Enable. 4. Pre-Shared Key is by default. 5. Click on Apply. Configure L2TP/PPTP Policy 1. Go to VPN > L2TP VPN/PPTP VPN > Setup. 2. Check Enable. 3. Enter IP Address Pool Click on Apply. Scenario x 8.1 Application scenario SBG series supports 802.1x. This feature provides IT managers with a solution to control the enterprise wireless environment. The wireless users require RADIUS authentication when they connect to the SBG SSID. 8.2 Configuration Guide Disable WPS 1. Go to Network Setting > Wireless > WPS. 17

18 2. Select WPS Disable. 3. Click on Apply. Configure 802.1x 1. Go to Network Setting > Wireless > General. 2. Select Wireless Enable. 3. Enter Wireless Network Name (SSID) (ex: ZyXEL). 4. Enter Max Clients (ex: 32). 5. Select Security Mode WPA/WPA2. 6. Enter IP Address (RADIUS Server). 7. Enter Port Number Enter Shared Secret Click on Apply. Scenario 9 Maintenance Log 9.1 Application Scenario Log file is an important method for IT Managers to monitor the device status. SBG Series has the capability to save the log to Local database, Remote Syslog Server and also inform user. 18

19 9.2 Configuration Guide Local File 1. Go to Maintenance > Log Setting. 2. Select Syslog Logging Enable. 3. Select Mode Local File. 4. Check Active Log and Alert Items (System, DHCP Client, etc.). 5. Click on Apply Remote/Local File and Remote 1. Go to Maintenance > Log Setting. 2. Select Syslog Logging Enable. 3. Select Mode Remote. 4. Enter Syslog Server Enter UDP Port Check Active Log and Alert Items (System, DHCP Client, etc.). 7. Click on Apply Log Settings Configure Notification 1. Go to Maintenance > Notification. 2. Click on Add New Enter Mail Server mail.zyxel.com.tw. 4. Enter Authentication Username test. 5. Enter Authentication Password Enter Account Address 7. Click on Apply. Configure Log Setting 1. Go to Maintenance > Log Setting. 2. Select Syslog Logging Enable. 3. Enter Mail Server mail.zyxel.com.tw. 4. Enter System Log Mail Subject SBG - System Log. 5. Enter Security Log Mail Subject SBG - Security Log. 6. Enter Send Log to admin@zyxel.com.tw. 7. Enter Send Alarm to admin@zyxel.com.tw. 8. Check Active Log and Alert Items (System, DHCP Client etc). 9. Click on Apply. 19

20 Chapter 4 Product FAQ: Will the device work with my Internet connection? SBG Series is designed to be compatible with major ISPs that utilize ADSL as a broadband service. SBG Series offers Ethernet ports to connect to your computer so the device is placed in the line between the computer and your ISP. Why do I need to use SBG Series? If you need an ADSL/VDSL modem/router to use with an ADSL/VDSL line, SBG Series is an ideal device for such application. The device has 4 Ethernet ports (LAN ports) and ADSL/VDSL WAN port. You should connect your computer to the LAN port and connect the ADSL/VDSL line to the WAN port. If the ISP uses PPPoE or PPPoA, you need a user account and password to access the Internet. What is PPPoE? PPPoE stands for Point-to-Point Protocol over Ethernet; it is an IETF draft standard specifying how a computer interacts with a broadband modem (i.e. xdsl, cable, wireless, etc.) to achieve access to the high-speed data networks via a familiar PPP dialer such as 'Dial-Up Networking' user interface. PPPoE supports a broad range of existing applications and services including authentication, accounting, secure access and configuration management. There are many service providers running of PPPoE today. Before configuring PPPoE in the device, please make sure your ISP supports PPPoE. Does the SBG Series support PPPoE? Yes. All SBG Series supports PPPoE. What is PPPoA? 20

21 PPPoA is short for Point-to-Point Protocol over Asynchronous Transfer Mode (ATM). PPPoA relies on two widely accepted standards: PPP and ATM. It is an end-to-end asymmetric digital subscriber line (ADSL) architecture. IP packets travel from the PC over Ethernet to the DSL modem, called the ADSL transceiver unit-remote (ATU-R). The ATU-R adds the PPP protocol to the IP packets and transports them to the carrier's Digital Subscriber Line Access Multiple (DSLAM) via ATM. It is a technology becoming more popular with DSL providers. Does the SBG Series support PPPoA? Yes. All SBG Series supports PPPoA. How do I know if I am using PPPoE/PPPoA? PPPoE/PPPoA requires a user account to log in to the provider's server. If you need to configure a user name and password on your computer to connect to the ISP you are probably using PPPoE/PPPoA. If you are simply connected to the Internet when you turn on your computer, you probably are not using PPPoE/PPPoA. You can also check with your ISP s hotline or check the information sheet provided by the ISP. Please choose PPPoE/PPPoA as the encapsulation type in the device if the ISP uses PPPoE/PPPoA. Why does my provider use PPPoE/PPPoA? PPPoE/PPPoA emulates a familiar Dial-Up connection. It allows your ISP to provide services using their existing network configuration over the broadband connections. Besides, PPPoE/PPPoA supports a broad range of existing applications and services including authentication, accounting, secure access and configuration management. Which Internet applications can I use with the device? Most common applications include MIRC, PPTP, ICQ, Cu-SeeMe, NetMeeting, IP/TV, RealPlayer, VDOLive, Quake, Quake II, Quake III, StarCraft, & Quick Time. How can I configure the device? a. By accessing the Telnet remote management-driven user interface for 21

22 easy remote management. b. Web browser Using the embedded web server for easy configuration. What can we do with the device? Browse the World Wide Web (WWW), send and receive individual , and download software. These are just a few of many benefits you can enjoy when you put the whole office on-line with the device. Does the device support dynamic IP addressing? The device supports either a static or dynamic IP address from the ISP. What is the difference between the internal IP address and the real IP address from my ISP? Internal IP addresses are sometimes referred to as virtual IP addresses. They are a group of up to 255 IP addresses that are used and recognized internally on the local area network. They are not intended to be recognized on the Internet. The real IP addresses from the ISP, instead, can be recognized or pinged by another real IP address. The device works like an intelligent router that routes between the virtual IP address and the real IP address. What DHCP capability does the device support? The device supports DHCP client (Ethernet encapsulation) on the WAN port and DHCP server on the LAN port. The device's DHCP client allows it to get the Internet IP address from ISP automatically if your ISP uses DHCP as a method to assign IP address. The device's internal DHCP server allows it to automatically assign IPs and DNS addresses to the clients on the local LAN. How do I use the reset button, and what parameters will be reset by the reset button? You can use a blunt pointed object (e.g. paperclip) and insert it into the little reset button hole beside the power connector. Press down the reset button and hold down for approx. 5 seconds, and the unit will be reset. When the reset button is pressed, all the device parameters will be reset back to the factory default settings, including password and IP address 22

23 (the default IP address is , default password is 1234). What network interfaces does the new device Series support? The new device Series supports auto MDI/MDIX 10/100M Ethernet LAN port to connect to the computer or Switch on LAN. How does the device support TFTP? In addition to the direct console port connection, the device support uploading and downloading of the firmware and configuration file using TFTP (Trivial File Transfer Protocol) over LAN. Can the device support TFTP over WAN? Although TFTP should work over WAN as well, it is not recommended because of the potential data corruption problems. What is Virtual LAN (VLAN)? A virtual LAN, commonly known as a VLAN, is a group of hosts with a common set of requirements that communicate as if they were attached to the same wire, regardless of their physical location. A VLAN has the same attributes as a physical LAN, but it allows for end stations to be grouped together even if they are not located on the same LAN segment. Network reconfiguration can be done through software instead of physically relocating devices. What is VLAN construction? VLANs are created to provide the segmentation services traditionally provided by routers in LAN configurations. VLANs address issues such as scalability, security, and network management. Routers in VLAN topologies provide broadcast filtering, security, address summarization, and traffic flow management. By definition, switches may not bridge IP traffic between VLANs as it would violate the integrity of the VLAN broadcast domain. Virtual LANs are essentially Layer 2 constructs, whereas IP subnets are Layer 3 constructs. In a LAN employing VLANs, a one-to-one relationship often exists between VLANs and IP subnets, although it is possible to have 23

24 multiple subnets on one VLAN or have one subnet spread across multiple VLANs. Virtual LANs and IP subnets provide independent Layer 2 and Layer 3 constructs that map to one another and this correspondence is useful during the network design process. When do I need to use NAT? a. Make local server accessible from the outside Internet. When NAT is enabled the local computers are not accessible from outside. You can use Multi-NAT to make an internal server accessible from outside. b. Support Non-NAT Friendly Applications Some servers providing Internet applications such as some IRC servers do not allow users to login using the same IP address. Thus, users on the same network cannot login to the same server simultaneously. What is NAT? NAT (Network Address Translation-NAT RFC 1631) is the translation of an Internet Protocol address used within one network to a different IP address known within another network. One network is designated as the inside network and the other is the outside. Typically, a company maps its local inside network addresses to one or more global outside IP addresses and "unmaps" the global IP addresses on the incoming packets back into local IP addresses. The IP addresses for NAT can be either fixed or dynamically assigned by the ISP. In addition, you can designate servers, e.g., a Web server and a Telnet server, on your local network and make them accessible to the outside world. If you do not define any servers, the NAT offers the additional benefit of firewall protection. In such case, all incoming connections to your network will be filtered out by the CPE, thus preventing intruders from probing your network. For more information on IP address translation, please refer to RFC 1631, The IP Network Address Translator (NAT). How does NAT work? According to the following figure, we define the local IP addresses as the 24

25 Internal Local Addresses (ILA) and the global IP addresses as the Inside Global Addresses (IGA). The term 'inside' refers to the set of networks that are subject to translation. The NAT operates by mapping the ILA to the IGA required for communication with hosts on other networks. It replaces the original IP source address (and TCP or UDP source port numbers) and then forwards each packet to the Internet ISP, thus making the packets appear as if they came from the NAT system itself (e.g., the CPE router). The CPE keeps track of the original addresses and port numbers, so the incoming reply packets can have their original values restored. What is IP Multicast? Traditionally, the IP packets are transmitted in two ways: unicast or broadcast. Multicast is a third way to deliver the IP packets to a group of hosts. Host groups are identified by class D IP addresses, i.e., those with "1110" as their higher-order bits. In dotted decimal notation, host group addresses range from to Among them, is assigned to the permanent IP hosts group, and is assigned to the multicast routers group. The IGMP (Internet Group Management Protocol) is the protocol used to support multicast groups. The latest version is version 2 (See RFC2236). The IP hosts use IGMP to report their multicast group membership to any immediate-neighbor multicast routers, so the multicast routers can decide if a multicast packet needs to be forwarded. At the start-up, the Prestige queries all directly connected networks to gather group membership. After that, the CPE updates the information by periodic queries. The device implementation of IGMP is also compatible with version 1. The multicast setting can be turned on or off on the Ethernet and remote nodes. What is BOOTP/DHCP? BOOTP stands for Bootstrap Protocol. DHCP stands for Dynamic Host Configuration Protocol. Both are mechanisms to dynamically assign an IP address to a TCP/IP client by the server. In this case, the device is a BOOTP/DHCP server. Windows 95 and Windows NT clients use DHCP to request an internal IP address, while WFW and WinSock clients use BOOTP. TCP/IP clients may specify their own IP or utilize 25

26 BOOTP/DHCP to request an IP address. What is DDNS? The Dynamic DNS service allows you to alias a dynamic IP address to a static hostname, allowing your computer to be more easily accessed from various locations on the Internet. To use the service, you must first apply for an account from one of several free Web servers such as Without DDNS, our users will always need to use the WAN IP address of the SBG Series to reach our internal server. It is inconvenient for the users if this IP is dynamic. With DDNS supported by the device, you can apply for a DNS name (e.g., for your server (e.g., web server) from a DDNS server. The outside users can always access the web server using the regardless of the WAN IP address of the SBG Series. When the ISP assigns the device (SBG Series) a new IP address, the device updates this IP address to the DDNS server so that of the server to update its IP-to-DNS entry. Once the IP-to-DNS table in the DDNS server is updated, the DNS name for your web server (i.e., remains usable. When do I need to use DDNS service? When you want your internal server to be accessed by using DNS name rather than using the dynamic IP address we can use the DDNS service. The DDNS server allows to alias a dynamic IP address to a static hostname. Whenever the ISP assigns you a new IP address, the device sends this IP address to the DDNS server to update its records. Introduction of QoS Quality of Service (QoS) refers to both a network s ability to deliver data with minimum delay, and to the networking methods used to control the use of bandwidth. QoS allows the ZyXEL device to group and prioritize application traffic and fine-tune network performance. Without QoS, all traffic data is equally likely to be dropped when the 26

27 network is congested. This can cause a reduction in network performance and make the network unfit for time critical applications such as video-on-demand. What is a Virtual Private Network (VPN)? VPN stands for Virtual Private Network. In the past, when we needed to transmit data in a secure way, we would need to have a site-to-site leased line between the sites. This incurred very high costs for installing the lines. A VPN gives users a secure way to access corporate network resources over the Internet or other public or private networks without the expense of leasing site-to-site lines. A secure VPN is a combination of tunneling, encryption, authentication, access control and auditing technologies/services used to transport traffic over the Internet or any insecure network that uses the TCP/IP protocol suite for communication. L2TP/IPSec VPN Overview The Layer 2 Tunneling Protocol (L2TP) is a tunneling protocol used to support virtual private networks (VPNs). However, it does not provide any encryption or confidentiality by itself; it relies on an encryption protocol that it passes within the tunnel to provide privacy. For this reason, L2TP is often implemented along with IPSec. This is referred to as L2TP/IPSec. IPSec VPN tunnel is established first and then an L2TP tunnel is built inside it. When the process is complete, L2TP packets between the endpoints are encapsulated by IPSec. Since the L2TP packets themselves are wrapped and hidden within the IPSec packets, no information about the internal private network can be garnered from the encrypted packets. Also, it is not necessary to open UDP port 1701 (used for L2TP) on firewalls between the endpoints, since the inner packets are not acted upon until after IPSec data has been decrypted and stripped, which only takes place at the endpoints. PPTP VPN Overview The Point-to-Point Tunneling Protocol (PPTP) is a method for implementing 27

28 VPN. It allows a user to create a secure VPN connection remotely to the local networks. The intended use of this protocol is to provide similar levels of security and remote access as typical VPN products. Wireless FAQ What is a Wireless LAN? Wireless LANs provide all the functionality of wired LANs, without the need for physical connections (wires). Data is modulated onto a radio frequency carrier and transmitted through the ether. Typical bit-rates are 11 Mbps and 54 Mbps, although in practice data throughput is half of this. Wireless LANs can be formed simply by equipping PC's with wireless NICs. If connectivity to a wired LAN is required, an Access Point (AP) is used as a bridging device. AP's are typically located close to the center of the wireless client population. What are the advantages of Wireless LANs? a. Mobility: Wireless LAN systems can provide LAN users with access to real-time information anywhere in their organization. This mobility supports productivity and service opportunities not possible with wired networks. b. Installation Speed and Simplicity: Installing a wireless LAN system can be fast and easy and can eliminate the need to pull cable through walls and ceilings. c. Installation Flexibility: Wireless technology allows the network to go where wires cannot go. d. Reduced Cost-of-Ownership: While the initial investment required for wireless LAN hardware can be higher than the cost of wired LAN hardware, overall installation expenses and life-cycle costs can be significantly lower. Long-term cost benefits are greatest in dynamic environments requiring frequent moves and changes. 28

29 e. Scalability: Wireless LAN systems can be configured in a variety of topologies to meet the needs of specific applications and installations. Configurations are easily changed and range from peer-to-peer networks suitable for a small number of users to full infrastructure networks of thousands of users that enable roaming over a broad area. What are the disadvantages of Wireless LANs? The speed of Wireless LANs is still relatively slower than that of wired LAN. The most popular wired LAN standard operates at 100 Mbps, which is more than 4 times of that of Wireless LAN (effectively around 25 Mbps). A faster wired LAN standard (1000 Mbps), which is 40 times faster, is becoming popular as well. The setup cost of Wireless LAN is relatively higher because the equipment costs which includes access points and Wireless LAN cards is higher than hubs and CAT 5 cables. Where can you find wireless networks? Airports, hotels, and even coffee shops like Starbucks are deploying networks so that customers can wirelessly access the Internet with their laptops. As these types of networks spread, this will create additional security risk for remote users if not properly protected. What is an Access Point (AP)? The AP (Access Point also known as a Base Station) is a wireless server with an antenna and a wired Ethernet connection that broadcasts information using radio signals. An AP typically acts as a bridge for the clients. It can pass information to wireless LAN cards that have been installed in computers or laptops allowing those computers to connect to the campus network and the Internet without wires. What is IEEE ? The IEEE is a wireless LAN industry standard, and the objective of IEEE is to make sure that different manufacturers' wireless LAN devices can communicate with each other provide 1 or 2 Mbps transmission data rates in the 2.4 GHz ISM band using either FHSS or 29

30 DSSS modulation. What is b? b is the first revision of standard allowing data rates up to 11 Mbps in the 2.4GHz ISM band. It is also known as High-Rate and Wi-Fi b only uses DSSS modulation, and the maximum speed of 11 Mbps has fallbacks to 5.5, 2 and 1 Mbps. How fast is b? The IEEE b standard has a nominal speed of 11 megabits per second (Mbps). However, depending on signal quality and how many other people are using the wireless Ethernet through a particular Access Point, usable speed will be much lower (on the order of 4 or 5 Mbps, which is still substantially faster than most dialup, cable and DSL modems). What is a? a is the second revision of that operates in the unlicensed 5 GHz band and allows transmission rates of up to 54 Mbps a uses OFDM (orthogonal frequency division multiplexing) modulation as opposed to FHSS or DSSS. Higher data rates are possible by combining channels. Due to higher frequency, range is less than lower frequency systems (i.e., b and g) and can increase the cost of the overall solution because a greater number of access points may be required a is not directly compatible with b or g networks. In other words, a user equipped with an b or g radio card will not be able to interface directly with an a access point. Multi-mode NICs can solve this problem. What is g? g is an extension of b g increases b's data rates to 54 Mbps and still utilizes the 2.4 GHz ISM band. Modulation is based upon OFDM (orthogonal frequency division multiplexing) technology. An b radio card will interface directly with an g access point (and vice versa) at 11 Mbps or lower depending on range. The range at 54 Mbps is less than for b operating at 11 Mbps. 30

31 What is n? n supports frequencies in both 2.4 GHz and 5 GHz radio bands and its data rate ranges from 54 Mbit/s up to 600 Mbit/s in theory, using the n Channel Doubling technology which can double the channel bandwidth from 20 MHz to 40 MHz and effectively doubles data rates and throughput. It adds the MIMO feature, which utilizes multiple transmission and reception antennas to allow higher raw data rate, and resolves more information than possible using a single antenna configuration n also uses the Alamouti coding coding scheme to increase transmission range. Is it possible to use products from a variety of vendors? Yes, as long as the products comply with the same IEEE standard. The Wi-Fi logo is used to define compatible products. What is Wi-Fi? The Wi-Fi logo signifies that a product is interoperable with wireless networking equipment from other vendors. A Wi-Fi logo product has been tested and certified by the Wireless Ethernet Compatibility Alliance (WECA). If a Wireless LAN Card is Wi-Fi certified, that means that it will work (interoperate) with any brand of Access Point that is also Wi-Fi certified. What types of devices use the 2.4 GHz band? Various spread spectrum radio communication applications use the 2.4 GHz band. This includes WLAN systems (not necessarily of the type IEEE b), cordless phones, wireless medical telemetry equipment and Bluetooth short-range wireless applications, which includes connecting printers to computers and connecting modems or hands-free kits to mobile phones. Does the interfere with Bluetooth devices? Any time devices are operated in the same frequency band, there is a potential for interference. Both the b and Bluetooth devices occupy the same 2.4-to GHz unlicensed frequency range-the same band. But a Bluetooth device 31

32 would not interfere with other devices much more than another device would interfere. While more collisions are possible with the introduction of a Bluetooth device, they are also possible with the introduction of another device, or a new 2.4 GHz cordless phone for that matter. But, Bluetooth devices are usually low-power, so the effects that a Bluetooth device may have on an network, if any, aren't far-reaching. Can radio signals pass through walls? Transmitting through a wall is possible depending upon the material used in its construction. In general, metals and substances with high water content do not allow radio waves to pass through. Metals reflect radio waves and concrete attenuates radio waves. The amount of attenuation suffered in passing through concrete will be a function of its thickness and the amount of metal reinforcement used. What are potential factors that may cause interference for WLAN products? Factors of interference: 1. Obstacles: walls, ceilings, furniture, etc. 2. Building Materials: metal doors, aluminum studs. 3. Electrical devices: microwaves, monitors, electric motors. Solution: 1. Minimize the number of walls and ceilings between clients and APs. 2. Position Antennas for best reception. 3. Keep WLAN products away from electrical devices, e.g.: microwaves, monitors, electric motors, etc. 4. Add additional APs if necessary. What is the difference between a WLAN and a WWAN? WLANs are generally privately owned, wireless systems that are deployed in a corporation, warehouse, hospital, or educational campus setting. Data rates are high and there are no per-packet charges for data transmission. WWANs are generally publicly shared data networks designed to provide coverage in metropolitan areas and along traffic corridors. WWANs are 32

33 owned by a service provider or carrier. Data rates are low and charges are based on usage. Specialized applications are characteristically designed around short, burst messaging. What is Ad-Hoc mode? A wireless network consists of a number of stations without access points or any connection to a wired network. What is Infrastructure mode? Infrastructure mode implies connectivity to a wired communications infrastructure. If such connectivity is required the Access Points must be used to connect to the wired LAN backbone. Wireless clients have their configurations set for "infrastructure mode" in order to utilize access points for relaying data. How many Access Points are required in a given area? This depends on the surrounding terrain, the diameter of the client population, and the number of clients. If an area is large with dispersed pockets of populations then extension points can be used for extend coverage. What is Direct Sequence Spread Spectrum (DSSS) technology? DSSS spreads its signal continuously over a wide frequency band. DSSS maps the information bearing bit-pattern at the sending station into a higher data rate bit sequence using a "chipping" code. The chipping code (also known as processing gain) introduces redundancy which allows data recovery if certain bit errors occur during transmission. The FCC rules the minimum processing gain should be 10, typical systems use processing gains of 20. IEEE b specifies the use of DSSS. What is Frequency Hopping Spread Spectrum (FHSS) technology? FHSS uses a narrowband carrier which hops through a predefined sequence of several frequencies at a specific rate. This avoids problems with fixed channel narrowband noise and simple jamming. Both transmitter and receiver must have their hopping sequences synchronized to create the effect of a single "logical channel". To an 33

34 unsynchronized receiver an FHSS transmission appears to be short-duration impulse noise may use FHSS or DSSS. Do I need the same kind of antenna on both sides of a link? No. Provided that the antenna is optimally designed for 2.4 GHz or 5 GHz operations. WLAN NICs often include an internal antenna which may provide sufficient reception. What is the 2.4 GHz frequency range? This frequency range has been set aside by the FCC, and is generally labeled the ISM band. A few years ago Apple and several other large corporations requested that the FCC allow the development of wireless networks within this frequency range. What we have today is a protocol and system that allows for unlicensed use of radios within a prescribed power level. The ISM band is populated by Industrial, Scientific and Medical devices that are all low power devices, but can interfere with each other. What is Server Set Identifier (SSID)? SSID is a configurable identification that allows clients to communicate to the appropriate base station. With proper configuration, only clients that are configured with the same SSID can communicate with base stations having the same SSID. SSID from a security point of view acts as a simple single shared password between base stations and clients. What is an ESSID? ESSID stands for Extended Service Set Identifier and identifies the wireless LAN. The ESSID of the mobile device must match the ESSID of the AP to communicate with the AP. The ESSID is an up to 32-character string and is case-sensitive. How do I secure the data across an Access Point's radio link? Enable Wired Equivalency Protocol (WEP) or Wi-Fi Protected Access (WPA) to encrypt the payload of packets sent across a radio link. What is WEP? 34

35 Wired Equivalent Privacy (WEP) is a security mechanism defined within the standard and designed to make the security of the wireless medium equal to that of a cable (wire). WEP data encryption was designed to prevent access to the network by "intruders" and to prevent the capture of wireless LAN traffic through eavesdropping. WEP allows the administrator to define a set of respective "Keys" for each wireless network user based on a "Key String" passed through the WEP encryption algorithm. Access is denied by anyone who does not have an assigned key. WEP comes in 40/64-bit and 128-bit encryption key lengths. Note that WEP was shown to have fundamental flaws in its key generation processing. What is the difference between 40-bit and 64-bit WEP? 40-bit WEP & 64-bit WEP are the same encryption level and can interoperate. The lower level of WEP encryption uses a 40-bit (10 Hex character) as "secret key" (set by user), and a 24-bit "Initialization Vector" (not under user control) (40+24=64). Some vendors refer to this level of WEP as 40-bit, others as 64-bit. What is a WEP key? A WEP key is a user defined string of characters used to encrypt and decrypt data. Can the SSID be encrypted? WEP, the encryption standard for , only encrypts the data packets, not the management packets; however, the SSID is in the beacon and probe management messages. The SSID is not encrypted if WEP is turned on. The SSID is transmitted over the air in clear text. This makes obtaining the SSID easy by sniffing wireless traffic. By turning off the broadcast of SSID, can someone still sniff the SSID? Many APs by default have broadcasting the SSID turned on. Sniffers typically will find the SSID in the broadcast beacon packets. Turning off the broadcast of SSID in the beacon message (a common practice) does not prevent getting the SSID, since the SSID is sent in the clear in the probe 35

36 message when a client associates to an AP. A sniffer just has to wait for a valid user to associate with the network to see the SSID. What are Insertion attacks? The insertion attacks are based on placing unauthorized devices on the wireless network without going through a security process and review. What is a wireless sniffer? An attacker can sniff and capture legitimate traffic. Many of the sniffer tools for Ethernet are based on capturing the first part of the connection session, where the data would typically include the username and password. An intruder can masquerade as that user by using this captured information. An intruder who monitors the wireless network can apply this same attack principle on the wireless. What is the difference between Open System and Shared Key of authentication type? Open System: The default authentication service that simply announces the desire to associate with another station or access point. A station can authenticate with any other station or access point using open system authentication if the receiving station designates open system authentication. Shared Key: The optional authentication that involves a more rigorous exchange of frames, ensuring that the requesting station is authentic. For a station to use shared key authentication, it must implement WEP. What is 802.1x? IEEE 802.1x port-based network access control is an IEEE (Institute of Electrical and Electronics Engineers) standard, which specifies a standard mechanism for authenticating, at the link layer (Layer 2), users' access to IEEE 802 networks such as Ethernet (IEEE 802.3) and Wireless LAN (IEEE ). For IEEE WLAN, IEEE 802.1x authentication can be based on username/password or digital certificate. 36

37 What is the difference between No authentication required, No access allowed and Authentication required? No authentication required disables 802.1X and causes the port to transition to the authorized state without any authentication exchange required. The port transmits and receives normal traffic without 802.1x-based authentication of the client. No access allowed causes the port to remain in the unauthorized state, ignoring all attempts by the client to authenticate. The switch cannot provide authentication services to the client through the interface. Authentication required enables 802.1x and causes the port to begin in the unauthorized state, allowing only EAPOL frames to be sent and received through the port. The authentication process begins when the link state of the port transitions from down to up, or when an EAPOL-start frame is received. The switch requests the identity of the client and begins relaying authentication messages between the client and the authentication server. Each client attempting to access the network is uniquely identified by the switch by using the client's MAC address. What is AAA? AAA is the acronym for Authentication, Authorization, and Accounting and refers to the idea of managing subscribers by controlling their access to the network, verifying that they are who they say they are (via login name and password or MAC address) and accounting for their network usage. What is RADIUS? RADIUS stands for Remote Authentication Dial-In User Service. RADIUS is a standard that has been implemented into several software packages and networking devices. It allows user information to be sent to a central database running on a RADIUS server, where it is verified. RADIUS also provides a mechanism for accounting. What is WPA? WPA (Wi-Fi Protected Access) is a subset of the IEEE i security specification draft. The key difference between WPA and WEP are user 37

38 authentication and improved data encryption. What is WPA-PSK? WPA-PSK (Wi-Fi Protected Access Pre-Shared Key) can be used if users do not have a RADIUS server but still want to benefit from WPA security, because WPA-PSK only requires a single password to be entered on wireless AP/gateway and wireless client. As long as the passwords match, a client will be granted access to the WLAN. What is WPA2? WPA2 (Wi-Fi Protected Access 2) offers a higher security level than WPA, because it introduces an AES-based algorithm and CCMP in it and offers stronger encryption then WPA uses (TKIP). WPA2 encryption keys that are used for each client on the network are unique and specific to that client. Eventually, each packet which is sent over the air is encrypted with a unique key. The higher security is enhanced with the use of a new and unique encryption key because there is no key reuse. 38