SIP Trunking Design Patterns SIP Forum SIPNOC 2013

Transcription

1 SIP ing Design Patterns SIP Forum SIPNOC 203 Robert Kinder

2 SIP ing Design Patterns SIP ing Design Patterns are reusable solutions for frequently occurring customer implementations. Similar concept to software engineering design patterns. Design Patterns are used by: BSS/OSS Order Entry and Provisioning systems. Sales Engineers for consultative sales and proposals. Network Engineers to customize a design. Nine Design Patterns described here. Calls to ABC Calls to DEF Calls to HIJ Calls to Calls to XYZ Calls to ABC Calls to XYZ ISDN PRIs CLASS 5 Switch SIP ISDN PRIs Calls to ABC Calls to XYZ Group Management Group Mgmt Shared Pool Capacity: DIDs: ABC DIDs: QRS DIDs: XYZ DID Ranges: ABC Route List:, 6, 7, 8 2 DID Ranges: DEF Route List: 2,, 6, 7, 8 3 DID Ranges: HIJ Route List: 3,, 6, 7, DID Ranges: XYZ Route List: 8 Group Mgmt DID Ranges Load Balancing / Routing Algorithm Group Route List Group Mgmt DID Ranges Load Balancing / Routing Algorithm Group Route List Group Mgmt Group Mgmt 2 DID Ranges: ABC DID Ranges: XYZ Route List: TG, TG 2 Route List: TG 2, TG Group Mgmt Group Mgmt DID Ranges: ABC Route List: TG, TG 2, TG3 Group Mgmt 2 DID Ranges: XYZ Route List: TG 2, TG, TG3 Group Mgmt 3 DID Ranges: n/a Route List: TG3 Group Trk Grp Capacity: 25 Trk Grp 2 Capacity: 35 Trk Grp 3 Capacity: 5 Trk Grp Capacity: 75 Trk Grp 2 Capacity: 50 Trk Grp 3 Capacity: 50 Trk Grp 8 Capacity: 50 Group 3 Group 4 Failover Routing Primary Failover Routing Final Failover Routing Group 3 Normal Ops: ABC Failover: XYZ Normal Ops: XYZ Failover: ABC Normal Ops: ABC Failover: XYZ Normal Ops: XYZ Failover: ABC 2 3 Office Office 2 Office 3 Office 2 Office 2 3 Office 3... Additional Office Locations 8 Office 8 SIP s SIP s Terminal Node Data Center Data Center 2 Data Centers in the Same Metro Area Branch Offices with Survivable Gateways Hot Standby Remote Site ISDN PRI ISDN PRI 2

3 Design Pattern Elements SIP Proxy, Call Features and Routing Provisioned Call Capacity Dial Plan, Call Policies, etc. Group Management Objects Telephone Numbers (DIDs) Group Load Balancing Algorithm Group Route List Cox SIP CPE & service demarcation in it s many varieties & configurations Account Provisioned Capacity ( Call Paths) Group Management Telephone Numbers (DIDs) Reroute Attempts Group Load Balancing Algorithm Group Route List Group Group ID Pilot Number Call Capacity (2-Way, Inbound/Outbound Only) Business Continuity Options: CFA, Unreachable Destination SIP s Premise 3

4 Group Basics One or more Group Management (TGM) objects Created as needed for DID-based call routing Can route calls to any Group One or more Groups Represents a trunk to a physical location () Exists independently of the TGMs... Quantity of Groups is based on: Locations Type of Product Capacity Redundancy Options Group Mgmt Group... Group Mgmt Group Group Mgmt Group SIP SIP SIP 4

5 SMB Design Pattern Small/Medium Business (SMB) One Group / One 5 to ~00 SIP s (concurrent call paths) Typically 5 to 50 trunks for ISDN PRI replacement Optional Burstable Capacity No access network link diversity Network-based Business Continuity Options: CFA and Unreachable Destination (contingency form of Call Forwarding) on the Group Group Mgmt Group 5

6 Multi-Site Shared s Cost optimization for Multi-Location SMB Each Branch Office has different DID ranges s can be different Oversubscribe a Shared Pool of Capacity e.g. 25% over-subscribe a shared pool of 60 trunks Capacity dynamically floats across all branch offices Burstable trunks to minimize call blocking Shared Pool Capacity: 60 DIDs: ABC Trk Grp Capacity: 25 2 DIDs: QRS Trk Grp 2 Capacity: 35 3 DIDs: XYZ Trk Grp 3 Capacity: Office Office 2 Office 3 6

7 Load Balanced SMB Two Groups and Dual s Requires config. for two trunks Better Reliability Eliminates single point of failure Each / sized to carry the full call load Access Network Link Diversity may be possible, e.g. fiber and coax Especially for folded fiber ring (fiber lacking path diversity) Load Balancing: Weighted or Ordered algorithms Group Mgmt 7

8 Multi-Site Overflow Geo-Redundancy on a Budget Example Use Case: A municipality has several departments each with a that wishes to maximize resources by having calls overflow to alternate sites. Easily configured via Group Route Lists Terminal Nodes (office locations) do not overflow to another Group Similar in concept to RAIN, Redundant Array of Inexpensive Nodes Office Locations / Groups Group Overflow Route List Terminal Nodes. Groups Do Not Overflow. 8

9 Multi-Site Overflow Pattern Calls to ABC Calls to DEF Calls to HIJ Calls to Calls to XYZ DID Ranges: ABC Route List:, 6, 7, 8 2 DID Ranges: DEF Route List: 2,, 6, 7, 8 3 DID Ranges: HIJ Route List: 3,, 6, 7, DID Ranges: XYZ Route List: 8 Trk Grp Trk Grp 2 Trk Grp 3 Trk Grp 8 Capacity: 75 Capacity: 50 Capacity: 50 Capacity: Additional Office Locations 8 Office Office 2 Office 3 Office 8 Terminal Node 9

10 Basic Geo-Redundancy & Network Diversity Any single Group can carry the full call load Automatic Reroute/Failover Load Balancing Algorithms: Weighted, Ordered, Overflow, Least/Most Idle Asymmetrical Data Center Capacity for MRC cost optimization: normal and burstable capacities e.g. Active/Standby Data Centers. Group Mgmt DID Ranges Load Balancing / Routing Algorithm Group Route List Group 3 Data Center Data Center 2 Group 4 0

11 High Availability Geo-Redundancy and Network Diversity High Availability Equipment Simplifies configuration with a single trunk route. Diverse Fiber Paths into Data Centers Most often deployed by Fortune 500, Gov t, Healthcare, Education & Financial Zero tolerance for outages Expectation that voice is always on, like water and electricity. Automatic Call Reroute/Failover Group Mgmt DID Ranges Load Balancing / Routing Algorithm Group Route List

12 DID Routing w/ Geo-Redundancy DID ranges apportioned by Data Center Optimizes Inbound Call Routing when most users/dids are co-located with one or the other Data Center Data Center typically is a main campus location Minimizes traffic during normal operations Active/Active Data Centers Automatic Failover to the alternate Data Center during an outage Calls traverse the to reach the other Data Center Calls to ABC Group Mgmt DID Ranges: ABC Route List: TG, TG 2 Normal Ops: ABC Failover: XYZ Failover Routing Calls to XYZ Group Mgmt 2 DID Ranges: XYZ Route List: TG 2, TG 2

13 SIP to ISDN PRI Failover SIP to Traditional PRI Failover. Packet to Circuit Switched Voice Service Provider Network and Platform Redundancy PRIs delivered on a different Layer 2 network for isolation from VoIP/IP impairments CLASS 5 Central Office acts like a railroad switch to redirect traffic from SIP to PRIs PRIs to Branch Offices with Survivable Gateways Can optionally failover just the most important DIDs for reduced cost and PRI capacity ISDN PRIs ISDN PRI CLASS 5 Switch Group Mgmt SIP s SIP Branch Offices with Survivable Gateways ISDN PRIs SIP s ISDN PRI 3

14 Design Pattern Comparison Matrix Group Design Patterns by increasing diversity: Design Pattern Groups Call Capacity CFA Unreachable Destination Small/Medium Business (SMB) 5 to 00 Multi-Site Shared s 20 to 00+ Load Balanced Group Business Continuity Options Automatic Route Advance Route Exhaustion Geo- Redundant High Availability Alternate Network & Platform Load Balanced SMB 2 20 to 00+ Multi-Site Overflow Basic Geo-Redundancy High Availability Geo-Redundancy DID Routing w/ Geo-Redundancy SIP to ISDN PRI Failover Minimum Call Capacity guidelines are driven by Return On Investment (ROI), rather than technical constraints. CFA and Unreachable Destination Group features are not used with multi-site overflow and geo-redundancy because it will short-circuit the route advance algorithm. 4

15 Summary Design patterns are a means to categorize and define standardized products. More design patterns are possible. Intercarrier reroute/failover. Design patterns are extensible: Three (3) versus two (2) geo-redundant data centers as shown in the examples for brevity. Elements of design patterns can be combined. 5

16 Extending a Design Pattern First two data centers are in the same Metro area (very common). At risk for hurricane, regional power outage, etc. 3 rd Data Center is hot standby at a distant location to mitigate a catastrophic metro event. Stateful Failover avoids post dial delay by removing unavailable sites from the route list. Group Mgmt DID Ranges: ABC Route List: TG, TG 2, TG3 Normal Ops: ABC Failover: XYZ Calls to ABC Primary Failover Routing Data Centers in the Same Metro Area Group Mgmt 2 DID Ranges: XYZ Route List: TG 2, TG, TG3 Calls to XYZ Final Failover Routing Normal Ops: XYZ Failover: ABC Group Mgmt 3 DID Ranges: n/a Route List: TG3 Group 3 Hot Standby Remote Site 6