>________________________________________ >From: [email protected] >[[email protected]] On Behalf Of Josh Roberts >[[email protected]] > >I'm trying to authenticate a statement by a voip/sip system integrator that >dhcp has stability and reliability issues because when the phone rings >(every time, according to this company) it has to check its lease for >renewal and potentially renew the lease before the call can connect. >_______________________________________________ [snip] >DHCP does *not* have stability and reliability issues in an environment that >implements DHCP >well -- that has coordinated, redundant DHCP servers, which almost every IP >network does. >DHCP is used in this manner by many, many enterprises, many of which have >hundreds or thousands >of IP phones. > >There may be certain specialized environments where using DHCP for VoIP phones >is not a good idea, >but you need to have someone explain exactly why.
The only case I can think of would be that an IP address change from the DHCP provider (think DSL) would cause existing RTP streams (and SIP registrations) to be invalid. A *good* implementation will re-REGISTER on IP change, and if there's a change during a call it can re-REGISTER, re-STUN/etc, and then re-INVITE with the new c= value. Note that most probably don't do the latter, and some may not do the former. This may be the reason, but it has nothing to do with ringing. They may be thinking of a device that's silent for long periods and might face a router/DHCP-server reboot, or they may have seen equipment that doesn't renew DHCP correctly. (Grasping at straws here - ask them) -- Randell Jesup, Worldgate (developers of the Ojo videophone) [email protected] _______________________________________________ Sip-implementors mailing list [email protected] https://lists.cs.columbia.edu/cucslists/listinfo/sip-implementors
