SIP deployment in LEARN Nimal Ratnayake <nimalr@learn.ac.lk> - - PowerPoint PPT Presentation

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SIP deployment in LEARN

Nimal Ratnayake

<nimalr@learn.ac.lk>

Lanka Education and Research Network (LEARN) and Department of Electrical & Electronic Engineering, University of Peradeniya

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Introduction

• LEARN: Lanka Educational and Research

Network

• Interconnecting academic/research

institutions within Sri Lanka

• Established in 1990
• Currently interconnects

– 13 universities (some with multiple campuses) – National Science Foundation – University Grants Commission

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SIP in LEARN

• SER
• Accounts to anyone within LEARN
• Preferred method to contact NOC
• Limited deployment so far, mostly for

contacting LEARN NOC

• Promotion

– Provide SIP phones to key persons (Vice- Chancellor etc) at each member institute – Build gateways to campus PBXs

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SIP at PDN

• Implemented sip.edu
• Integrated PBX and SIP based VoIP
• Direct Inward Dialling from PSTN
• All new telephones will be SIP phones

– Cheaper than Cabling+equipment cost for a PBX extension

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SIP at PDN(2)

SER Cisco 3640 Ericsson MD110 ISDN PRI PSTN Radius LDAP MySQL Call logging VoIP

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Components used

• Open Source/Free SW plus costly hardware

– SER – Cisco 3640 w/ ISDN PRI link to PBX as gateway – Ericsson MD100 PBX with MFC R2 link to PSTN – OpenLDAP for campus directory – FreeRARIUS for authentication – MySQL for SER databases and accounting – Perl Scripts for LDAP Lookup/Call Logging – Grandstream BT102/GTX1000 and x-lite UAs

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SIP call handling

• REGISTER

– Radius authentication – Radius server looks up the LDAP directory for password – SER module uri_db with trivial modifications

• Allows nimalr@pdn.ac.lk to register as

1600@pdn.ac.lk

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SIP call handling (2)

• INVITE

– Use Perl script to do LDAP lookup for call forking to PBX extension – sip:nimalr@pdn.ac.lk becomes sip:nimalr@pdn.ac.lk plus sip:3423@pdn.ac.lk – On call failure (timeout, not found), lookup LDAP directory again for redirection to mobile

• Security

– All requests to gateway must go through SER – Proxy authentication for all outside calls

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Accounting

• Use MySQL for storing call logging from

PBX and Cisco gateway

• Two simple daemons written in Perl

– capture text call logging information from PBX – Capture Radius accounting packets from gateway – Both PBX and VoIP calls go to the same user account

• Users can check their usage on line

To do

• Asterisk for Voice Mail. IVR etc
• H.350 directory
• Gateways at other Universities
• LEARN gateway to PSTN
• Private ENUM tree for LEARN