Sprint PCS is in development of their "Push to Talk" product for walkie-talkie style service for their customers. SIP is being used for call setup and other controll funtions.
SIP is running on the handset itself and SIP proxy servers located at Sprint's distribution centers connecting to PTT Aplications Servers. Although troubleshooting becomes easier due to ASCII based messages used for negotiation (easily "read" with a sniffer), the protocol is "heavy" for CDMA (LOTS of activity) which is used on the PCS network. Other enhancements are being used to reduce latency with call setup and floor control during a session that ironicly are not SIP based i.e. using the RTP stream for control functions and some fancy buffering to improve the user experience. ----- Original Message ----- From: "nrf" To: Sent: Wednesday, March 05, 2003 9:50 PM Subject: Re: IP Telephony SIP [7:64433] > SIP servers - Sonus, Clarent (I think), Nortel, Indigo, guys like that. > > SIP phones used by providers - practically none. Dont' get me wrong - there > are SIP phones out there. But phones are not really the point of SIP. SIP > is a generalized control plane that extends far and beyond phones. Right > now, SIP is mostly being exploited by mobile carriers for back-end > interoperability. SIP is also being exploited to facilitate rich instant > messaging (consider RFC 3428). > > > ""supernet"" wrote in message > news:[EMAIL PROTECTED] > > Thanks. What SIP servers and SIP phones do service providers use? > > > > -----Original Message----- > > From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of > > nrf > > Sent: Tuesday, March 04, 2003 10:03 PM > > To: [EMAIL PROTECTED] > > Subject: Re: IP Telephony SIP [7:64433] > > > > ""supernet"" wrote in message > > news:[EMAIL PROTECTED] > > > Can anyone kindly enough tell me why SIP is better than CCM? What's > > the > > > main difference between this two? Is there any SIP in production? > > > Thanks. Yoshi > > > > You shouldn't compare SIP and CCM. SIP is an industry standard, whereas > > CCM > > is a Cisco product. Any vendor, including Cisco, can and has > > implemented > > SIP. Only Cisco can 'implement' CCM (after all the first 'C' stands for > > Cisco). > > > > There is a significant amount of SIP in production - almost all of it in > > service-providers. Most of today's 3G wireless networks, for example, > > rely > > on SIP. > > > > To make things more confusing, Cisco may implement SIP within CCM soon. Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=64608&t=64433 -------------------------------------------------- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
