these extensions are described in section 4. · RFC A Message Summary and Message Waiting Indication Event Package . Find the most up-to-date version of IETF – RFC at Engineering Find the most up-to-date version of RFC at Engineering
|Published (Last):||25 June 2005|
|PDF File Size:||12.89 Mb|
|ePub File Size:||2.64 Mb|
|Price:||Free* [*Free Regsitration Required]|
These include an efficient use of the ietr interface by minimizing the exchange of signaling messages between the mobile terminal and the network, a minimum session setup time by performing rcc prior to session establishment instead of during session establishment, a minimum support required in the terminal, the support for roaming and non-roaming scenarios with terminal mobility management supported by the access network, not SIPand support for IPv6 addressing.
CounterPath Corporation is a leading provider of innovative desktop and mobile VoIP software products and solutions. Service Discovery XEP To obtain transmission resources, the user agent must present an authorization token to the network i. For customers interested in purchasing units or less of our Bria softphone clients, please visit our online store.
These two extensions allow users to rcc their preferences about the service the IMS provides.
ITU-T A.5 reference justification
In this concept the caller states a set of constraints about the session i. They rfcc commonly obtained during the registration process: Stream Compression XEP Interested in buying Bria for Windows? There exist analogous extension headers for handling the identification of services of users,  instead of the users themselves. Retrieved 5 December Tell us a bit about yourself and receive additional information about our solutions and how they can be customized to meet your specific needs.
Network address translation NAT makes it impossible for a terminal to be reached from outside its private networksince it uses a private address that is mapped to a public one when packets originated by the terminal cross the NAT. PRACK, which is 325 request message used to tell the sender of a provisional response that his or her message has been received.
CounterPath Involvement in IETF for SIP Open Standards | CounterPath
This extension is only applicable within administrative domains with trust relationships. The functionality of sending instant messages to provide a service similar to text messaging is defined in the instant messaging extension.
There are several standards that address this requirements, such as 365 following two for services interworking between the PSTN and the Internet i. Moreover, there is also a mechanism for conditional event notification that allows the notifier to decide whether or not to send the complete NOTIFY message depending on if there is something new to notify since last subscription or there is not.
Current information, if any, about IPR issues:. This functionality is supported by the new MESSAGE method, that can be used to send an instant message to the resource stated in the request-URI, iftf the content carried in the message body.
To solve this problem, the concept of preconditions  was introduced. Clear description of the referenced document: To achieve this goal, SIP messages can be compressed using the mechanism known as SigComp ietv signaling compression.
ITU-T work programme
The private extensions for asserted identity within trusted networks  are designed to enable a network of trusted SIP servers to assert the identity of authenticated users, only within an administrative domain with previously agreed policies for generation, transport and usage of this identification information.
Feedback Contact Us Accessibility. In the IMS framework it is fundamental to handle user identities for authentication, authorization and accounting purposes. The efficient use of network resources, which may include a radio interface or other low-bandwidth access, is essential in the IMS in order to provide the user with an acceptable experience in terms of latency. Therefore, a mechanism is needed in order to route requests to the desired device or application.
With the caller preferences extension,  the calling party is able to indicate the kind of user agent they want to reach e. SIP is an exceptionally popular and extensible protocol. These header fields are used for a variety of purposes including charging and information about the networks a call traverses:. Finally, when privacy is requested, proxies must withhold asserted identity information outside the trusted domain by removing P-Asserted-Identity headers before forwarding user requests to untrusted identities outside the Trust Domain.
Therefore, NAT traversal mechanisms are needed for both the signaling plane and the media plane. They were designed specifically to meet the 3GPP requirements because a more general solution was not available. In a first approach, this dictionary may be built for each message by the compressor and sent to the decompressor along with the message itself. There are several mechanisms to achieve this, such as:. The event notification framework defines how a user agent can subscribe to events about the state of a resource, but it does not specify how that state can be published.
Combining voice and video calls in a user-friendly interface, CounterPath’s X-Lite helps you seamlessly transition from a traditional phone environment into the world of Voice over IP. The reliability of provisional responses extension  provides a mechanism to confirm that provisional responses such as the Ringing response codethat lets the caller know that the callee is being alerted, are successfully received.
Any explicit references within that referenced document should also be listed: Retrieved December 3, Likewise, if the server does not support any of the client’s required extensions, it will send an error response with a list of its unsupported extensions.
SIP and Open Standards
To indicate that the user agent requests or supports reliable provisional responses, the rel option tag will be used. The degree of stability or maturity of the document: In this case, Uniform Resource Names are used to identify a service e.
Software Version XEP Other for any supplementary information:. However, in such an scenario as the IMS framework, it is necessary to extend this reliability to provisional responses to INVITE requests for session establishment, this is, to start a call.
Relationship with other existing or emerging documents: This establishment will occur if and only if both the caller and the callee agree that the preconditions are met. The extension for service route discovery during registration  consists of a Service-Route header field that is used by the registrar in a 2XX response to a REGISTER request to inform the registering user of the entity that must forward every request originated by him or her.
This token will be obtained from its P-CSCF, which may be in charge of QoS policy control or have an interface with the policy control entity in the network i. Moreover, the SIP INFO method extension is designed to carry user information between terminals without affecting the signaling dialog and can be used to transport the dual-tone multi-frequency signaling to provide telephone keypad function for users.
Source routing is the mechanism that allows the sender of a message to specify partially or completely the route the message traverses. The security mechanisms agreement extension for SIP  was then introduced to provide a secure mechanism for negotiating the security algorithms and parameters to be used by the P-CSCF and the terminal.