content and concepts INdigital telecom INdigital SIP trunk interconnection a whitepaper guide to sip trunk connections to the INdigital network Issued as a part of the INdigital telecom network notes series Version 1.7 (13-267) last edit: 25 September 2013 09:05
Overview: This paper describes the various options a telecom service provider can use to establish SIP trunk based connections to the INdigital network. SIP interconnection allows service providers to deliver E911 calls for service to the INdigital 911 network, which will then result in the call being routed to the appropriate answering point. INdigital s network is based on the RFC-3261 standard, generally available at the IETF website: http://tools.ietf.org/wg/sip/ INdigital also supports: RFC-3262, RFC-3264, RFC-3311, RFC-3323, RFC-3325, RFC-3326, RFC-3398, RFC-3515, RFC-3525, RFC-3761, RFC-3824, RFC-3891, RFC-4028, RFC-4317, RFC-4488, RFC-4566, and RFC-4694. If the need arises to support services and protocols such as 183 - early media or provisional ACKs, these specifics can be negotiated per interconnect development, and a suitable technology bridge will be proposed and developed to meet your party s needs. 1) SIP Interconnection specifics: A). Transport Facilities: INdigital can support many different transport providers and has interconnection to many multicarrier facilities, Eline/Elan, P2P, MPLS or VPN are just a few of the connection options available. Development Environments: Secure IP tunnels(vpn) over commodity internet connections can be supported, and may be used for development or testing work. Production Environment: INdigital recommends a dedicated, private connection arrangement. The service provider s transport facility can terminate to any of INdigital s POP locations. A list of these locations is available to our business partners. INdigital recommends the use of redundant and diverse facility arrangements and redundant hardware where possible to maximize resiliency and reduce any single point of failure. Preferred to two points of geo-diverse private connections with an internet based VPN backup. 2 of 11 content and concepts INdigital telecom
Minimum requirements are one point of interconnection via private connection (T1-Data, Ethernet, MPLS, Eline/Elan) other connection can be private connection or VPN via internet. B). Transport Protocol: The INdigital network currently supports IPv4 connections. IPv6 is not supported at this time due to the immaturity and emerging support of the protocol. C). SIP Termination: The INdigital network has multiple SIP Session Boarder Controllers (SBC) available for SIP termination. SIP termination is, however, an inexact science, and the exact method will need to be engineered on a case by case basis, thereby defining the method of interconnection. D). Security Measures: INdigital requires that the Carrier use some form of Session Border Control at the Network Handoff Location. Primarily used for topology hiding, RTP proxy and normalization of the SIP protocol. If the interconnecting company cannot provide such SBC functionality, INdigital can consult on or suggest a configuration that will be supported. E). Call Signaling: SIP Call Signaling will use 911 as the called party number in cases where the ESN is not already known, i.e. for calls that are non-preselective routed. The Calling Party number or P-ANI/ESRK or ANI can be used if the ESN of the Emergency Services Agency is known. The ESN can be signaled using INdigital s ESN number as the called party. Currently only Called and Calling party fields are used for selective routing within the IN911 network. These configurations are negotiated on a per interconnection basis. F). Geo-Routing: For information regarding the ability to geo-route calls using PIDF-lo body or header fields, contact INdigital for an expanded discussion of this service feature, which is defined in RFC-2778 and RFC- 4119. These configurations are negotiated on a per interconnection basis. 3 of 11 content and concepts INdigital telecom
2) INdigital SIP Profile: SIP methods supported SIP timer values used SIP OPTIONS pings supported? Support/require PRACK? SBC Vendor/Model/Software Version Support/require Early Media? Calling Party one of the following: From: P-Asserted-ID:, Remote-Party-ID: Called Party (To:) RTCP DTMF Relay ACK, BYE, CANCEL, INVITE, OPTIONS (required) T1 500ms; T2 4sec; T4 5sec Yes No ACME Packet Net-Net or Similar Egress CPE/Gateway dependent Caller DN or ESRK of calling party preferred Agreed upon per connection Optional RFC-2833 or in-band 4 of 11 content and concepts INdigital telecom
3) INdigital Media Profile: Supported codecs Sampling rate UDP/TCP G.711u 20ms UDP (unless otherwise agreed) Port Signaling 5060 RTP port range 10000-29999 Support transcoding of media? RTCP enabled? Expected network delay for RTP No This is user agent specific, certain CPE/Gateways will support it, but not all. Internally <40ms. However, we are a large network using multiple transport types. 4) SIP Message Example Available upon request. 5 of 11 content and concepts INdigital telecom
6 of 11 content and concepts INdigital telecom
INdigital contacts INdigital SIP trunk service provider interconnection Parties needing additional information about IN911 SIP trunking or other inquiries regarding 9-1-1 trunking are invited to write or call: Brent Cummings, Director of Operations bcummings(at) indigital.net or Kent Claussen, Chief Technical Officer Kclaussen(at) indigital.net or Bobbie Carter, Project Manager Bcarter(at) indigital.net INdigital Telecom 1616 Directors Row Fort Wayne IN 46808 7 of 11 content and concepts INdigital telecom
Glossary of Terms ANI: Automatic Number Identification, describes the actual telephone number of a calling party. CPE: Customer Premises Equipment DTMF: Dual-tone multi-frequency signaling ESN: Emergency Service Number, a numerical identification for a specific emergency service provider. In this case used to assist in routing Emergency Calls for Service. ESRK: Emergency Service Routing Key. This generally describes a nondialable telephone number used as a record reference number for looking up caller location information for wireless, or similar nomadic type calls, for emergency services. See also P-ANI Gateway: An entrance point from one network to another G.711u: The default modulation scheme for Internet Protocol (IP) private branch exchange (PBX) vendors. G.711 digitizes analog voice signals. IETF: Internet Engineering Task Force. A standards setting body for the development and adoption of recommended standards defining IP and SIP protocols (among others.) INdigital network: A private IPv4 voice and data network owned and operated by INdigital telecom. The network can receive, selectively route and deliver E9-1-1 telephone calls (public to authority) to emergency communications centers throughout the state of Indiana using VoIP technology. IP: Internet Protocol. Also referred to as IPv4 in this white paper to specify that the network operates using Internet Protocol version 4. P-ANI: Pseudo Automatic Number Identification. See also ESRK PIDF-LO: Presence Information Data Format Location Object. (See also RFC 2778 and RFC 4119) POP: Point of Presence PRACK: Provisional Response Acknowledgement 8 of 11 content and concepts INdigital telecom
RFC: Request For Comments a distributed method of the development of standards used by the IETF. RTP: Realtime Transport Protocol RTCP: RTP Control Protocol SBC: Session Border Controller, is a network element used in VoIP networks to exert control over the signaling (and usually the media streams) involved in setting up, conducting, and tearing down telephone calls or other interactive media communications. SIP: Session Initiated Protocol T-1: A digital transmission link with a signaling speed of 1.544 Mbps. UA: User Agent UBE: Unified Border Element VoIP: Voice over Internet Protocol 9 of 11 content and concepts INdigital telecom
Appendix A This appendix contains the physical address and NPA-NXX of the IN911 SIP gateways. This appendix is for preliminary planning purposes only. The information needed to place orders for interconnection will be provided upon successful validation of the Carriers ability to meet the requirements of IN911 network operator for security and interconnection stability. 1. INdigital telecom 1616 Directors Row Fort Wayne, IN 46808 260-469-2010 The information contained in this appendix is 2. INdigital telecom VZ Main POP 303 E Berry St Fort Wayne, IN 46802 260-402 3. New Paris Telephone Inc. 19066 Market St New Paris, IN 46553 574-831 Private and Confidential. 4. Mulberry Cooperative Telephone Co., Inc. 123 S Glick St Mulberry, IN 46058 765-296 5. Pulaski White Rural Telephone Cooperative, Inc. 5573 S. US Hwy 35 Star City, IN 46985 574-595 text can be released-to-view in the original document 10 of 11 content and concepts INdigital telecom
6. Enhanced Telecommunications 123 Nieman St Sunman, IN 47041 812-623 7. PSC 11877 E. State Road 62 St. Meinrand, IN 47577 812-357 INdigital SIP trunk service provider interconnection text can be released-to-view in the original document Certain information contained in this appendix is Private and Confidential. 11 of 11 content and concepts INdigital telecom