MIT SIP.edu Installation
MIT implemented SIP.edu on March 20, 2003. Over 12,000 mit.edu email
addresses were mapped to PBX phone numbers in the initial installation.
In December 2005 the the SIP infrastructure was migrated from Pingtel
SIPxchange to OpenSER. Information on the original Pingtel
MIT is using
for its SIP proxies running on RedHat Linux
Enterprise servers. Our implementation utilizes three functional
types of SIP proxies.
Directory lookups are done from OpenSER to our LDAP directory running on
. MIT is currently using a Cisco 3825 gateway with two PRIs to our
Lucent 5ESS PBX.
- Outgoing Proxy - provides authentication and
authorization functions, and ensures preferred routing for MIT SIP
clients. Redundancy is provided through an F5 load balancer.
- Internal Proxy - provides connectivity to the
PSTN gateway and ensures external SIP issues do not impact internal
MIT SIP traffic and clients. Redundancy is provided through DNS SRV
- DMZ Proxy - provides SIP connectivity to external
clients outside of MIT, and provides isolation for internal MIT
clients to ensure external anomalies do not affect internal MIT
clients. Redundancy is provided through DNS SRV records.
Our implementation also uses
for voice mail and voice mail to email forwarding;
AG Projects Media Relay
for NAT traversal; and
MIT has developed web pages for configuration and feature
activation for both users and administrators. These are built using
Apache and Oracle and use X.509 certificates for authentication. A
configuration server is used to configure hard phones "out of the
box". Currently the line of Polycom SIP phones are supported for
9/29/06 - firstname.lastname@example.org