IP Telephony call routing and dial plan

• Monash University number ranges
• Number portability implications
• New telephone services
• Moving locations
• Toll bypass vs. Caller ID

Monash University number ranges

Number portability implications

The new IP Telephony service is flexible with number portability. When a user moves between campuses (either temporarily, or permanently) they can keep the same phone number.

When using a phone number at a different campus external calls will still be routed in or out at the original campus. For example, if a user with the phone number 39001 (Parkville) were to use extension mobility to login to a phone at Frankston, and someone outside Monash called them the call would enter the Monash network at Parkville and then be re-routed through the Monash network to Frankston. Likewise, if the same user at Frankston using extension to 39001 was to make an external call it would be routed through the Monash network from Frankston to Parkville and then out through the Telstra network.

This will all happen transparently to users. This behaviour will sometimes affect call costs (eg when a Clayton phone number is used to call an external Gippsland number, or calling numbers near Frankston just outside the Melbourne call zone). In the unlikely event of a failure of the Monash Wide Area Network (WAN) links between campuses people who are at a different campus to their extension prefix will also become unreachable.

New telephone services

When a new phone number is requested it will be allocated from one of the number ranges above based on the campus the request is coming from.

Moving locations

When staff move campuses they will have the option of keeping the same phone number, or requesting a new number in the new location.

Toll bypass vs. Caller ID

Telstra will only honour the Caller ID number provided by Monash if it comes out the correct gateway. For example, extension 51111 (+61 3 990 5111) is based at Clayton. If Monash sends a call from this number out through the Clayton Telstra exchange then Telstra will honour this calling party number and provide it to the called party (if they can receive caller ID). If Monash were to send the same call (from 51111) out through the Berwick campus to the Berwick Telstra exchange, then Telstra would rewrite the number causing a loss of Caller ID functionality.

This behaviour means that for certain calls Monash has to make the decision between preserving Caller ID and paying STD call charges, or breaking Caller ID and only paying the cost of a local call.

Monash tries to preserve Caller ID where possible. This may cause call costs to vary.