SOFTWARE DEFINED NETWORKING (SDN): A REALISTIC EVALUATION

Transcription

1 NTT Communications Group! NTT America, Inc.! SOFTWARE DEFINED NETWORKING (SDN): A REALISTIC EVALUATION Presented by: Shawn Morris shawn@ntt.net ショーン モリス NTT America Copyright 2013 NTT Communications Corporation. All Rights Reserved. 1

2 What is SDN? n Software-defined networking (SDN) is an approach to networking that centralizes control of the network by separating the control logic to off-device compute resources. This enables operators to use programmable control to orchestrate and automate network services without having to physically access the network s hardware. SDN Central Copyright 2013 NTT Communications Corporation. All Rights Reserved. 2

3 What is SDN? n Software-defined networking (SDN) is an approach to networking that centralizes control of the network by separating the control logic to off-device compute resources. This enables operators to use programmable control to orchestrate and automate network services without having to physically access the network s hardware. SDN Central Copyright 2013 NTT Communications Corporation. All Rights Reserved. 3

4 Intro to NTT GIN SDN or 3 W s and an H 4

5 Who? n NTT Global IP Network (AS2914) n Wholesale IP transit network l 150+ ibgp nodes l 70+ nodes running full-mesh RSVP-TE l Pseudo-wire Ethernet service available between all nodes l Bulk of customer ports are 10GE (or Nx10GE) l Present on 5 continents l Present in 31 markets

6 What? n Fully automated network operation n Homegrown tools l Organic, not a funded project n Almost to full SDN. n Roughly 200 other devices managed by SDN System (configtools)

7 Why? n IP Transit pricing experiences a consistent downward pressure. l Underlying costs must be managed in a similar fashion n Operating Expenses are kept low through a large degree of automation l Minimize peer review l Lower staffing requirements l Extensive reporting capabilities n Higher quality of service l Lower error rates (esp. catastrophic errors) n Improved service delivery l Consistency l Speed (both install and migration) l Customer initiated n Extensive network visibility

8 Global IP Network Map Q4/2004

9 Global IP Network Map Q4/2013 Q3/2010

10 How? n Database driven configuration management system n The network is modeled in the database. n Data from the database is transformed into device-ready configurations. n Server-side configuration is canonical. l No persistent manual configuration on devices.

11 Configtools Technology n PostgreSQL n GNU Make n M4 macros n bgptool homegrown binary l Includes custom M4 processor n Plain text file for each router kept in revision control n Custom scripts built on RANCID for pushing configurations to routers n RANCID collecting configuration hourly l Still useful for historical purposes

12 What is in the templates? n Standard ACLs n Standard device parameters l AAA configuration l SNMP l Logging n Interface parameters n Routing policy n Can include router OS version dependent options

13 What are the router requirements? n SSH access n Ability to retrieve files via FTP n Commit/roll back/roll forward capapility n If lacking the above, ability to directly manipulate the startup configuration l Devices only supporting this model are no longer considered for deployment in the Global IP Network

14 What s in the Configtools database? Management Interfaces MPLS Routing BGP OSPF ISIS PWE RSVP-TE LSP RSVP LDP SONET MAC Accounting Ethernet LAG Virtual Interfaces IP Addressing OOB Ports Standard ACL ASN Information SNMP Communities Copyright 2032 NTT Communications Corporation. All 14

15 What s in the plain text PLATFORM(hfr,mcast)dnl SERVICES(`loopback0')dnl! dnl dnl NETFLOW must be defined before Copyright 2012 NTT Communications Corporation. All Rights Reserved. 15

16 What was in the plain text file? include(`jnx.m4')dnl define(`myloop',` ')dnl PLATFORM(juniper,martini)dnl # # Verio / PAIX Palo Alto, CA Unauthorized Access is Prohibited # pao6.verio.net For Service Call (800) SERVICES()dnl NAMESERVERS()dnl LOGGING()dnl USERS()dnl SNMP(,`PAIX')dnl # interfaces { so-1/0/1 { description "BB: pvu0 p PAIX c34-r4-s3-s-b2b-b /mfs o2-brt-u /q spa /eli ocobgl elg"; clocking external; encapsulation cisco-hdlc; } sonet-options { fcs 16; payload-scrambler; } unit 0 { } point-to-point; family inet { no-redirects; } address /30; COST(13, `so-1/0/1', `BB: pvu0 p ')dnl PIMMODE(`sparse-dense', `so-1/0/1.0', 1) NTT America Confidential 16

17 Config Tools Workflow SQL Database M4 Macros Config File Router 1. User enters config changes via Web UI or CLI 2. User initiates config build via UNIX make command on configuration server 3. User initiates config push via UNIX command 1. Router is contacted by script via SSH 2. Router requests configuration from server via FTP 3. Configuration is committed Copyright 2012 NTT Communications Corporation. All 17

18 What kind of applications does this enable? n Automatic customer BGP ACL and max prefix updates n Tool to load peer/customer configurations on IOS l All relevant config (ie. interface, BGP neighbor, policy) is loaded via copy ftp: running-config n Mass update of RSVP-TE LSPs n Bulk move of interfaces/sub-interfaces n Seeding of other systems with data (stats system, monitoring system, etc.) n Complex configurations across multiple devices

19 What about my network?

20 Does SDN have a place in the carrier network? n YES! l Maybe OpenFlow/PCE/i2rs/etc. do too, but that s not what we re talking about today. n NTT GIN is not full SDN, yet tremendous benefits are still being realized. n Automation is the future. n Implementation can be incremental.

21 What do I need to know? n There are no magic bullets. n There will be custom development work. n Avoid the PeopleSoft problem n Requires a cultural shift.

22 Build or Buy? Homegrown n Upfront development costs n Need to staff software development expertise. n Ultimate in flexibility. n No vendor lock-in. n Support for new hardware and software on your schedule. n Possible organizational challenges. n Some COTS components to ease the custom work. n Could be hard to staff COTS n Upfront software costs n Possible costly consulting/customization costs n PeopleSoft problem potential n Potential vendor lock-in n At the mercy of the vendor for software and hardware support

23 Impacts on Organizational Culture n Some organizations/employees may feel they are being automated out of a job l Automating where possible frees up employees for more engaging and rewarding work n Given the shift to heavy tool use in the network, power struggles could occur. n A tight integration between network and software developers makes for the best results l Familiarity with the other s problem space is extremely valuable n Support from systems administrators can be critical

24 Impacts on Operational Culture n Network operators shift from having to know configuration knobs to knowing the systems. n Network operators must learn to think of the network at a service level. l Things must still be fixed when they break. l Teams must be cognizant of skill rot. l Network operators are more effective when they understand the operation of the tools.

25 Impacts on Equipment Selection n Integration with SDN toolsets becomes of paramount importance. n Some vendors may willingly or unwillingly remove themselves from contention. n Using COTS may further narrow choices. n Integrating a new platform may become easier.

26 Pitfalls n Supporting hacks solutions may become more difficult l Hacks solution can become landmines n Costs can quickly spiral out of control if not closely managed n If not well thought out, it can give others destructive access to your network

27 Conclusion n Automation is the way forward l It remains to be seen whether the concept of SDN will persist n The tools are getting better everyday n You can do this!

28 Obrigado