| SIP - the open standard, and Skype - | | | | which distinguish it from SIP. |
| closed. But Skype adapts for real | | | | First, report Skype is focused on a |
| conditions better, SIP it is focused on | | | | p2p-network (Peer-To-Peer.) Skype works |
| conditions relatives to ideal. | | | | by a principle self-organizing |
| Report SIP, Session Interaction Protocol | | | | distributed(allocated) p2p networks in |
| (RFC 3621) is open by a cavity for | | | | which there are no constant servers. The |
| developers. It(he) is well enough | | | | role of servers is carried out by the |
| thought over, and at the present moment | | | | participants of a network having direct |
| is the most popular as it is simple | | | | IP-address and the wide channel of |
| enough for hardware realization and, | | | | connection to the Internet. |
| besides the organization of voice | | | | Second, in report Skype enciphering is |
| sessions of communication(connection), | | | | without fail applied. It is the |
| gives a number(line) of additional | | | | compelled measure caused by |
| opportunities. Into problems(tasks) of | | | | p2p-structure of network Skype: the |
| report SIP enters only to establish and | | | | traffic passes through units to which |
| coordinate communication(connection), | | | | should not trust. |
| and it is not necessary that this | | | | Thirdly, Skype has the high |
| communication(connection) was voice is | | | | resourcefulness allowing it(him) to work |
| there can be any stream of the data in | | | | even on limited connections to the |
| real time - video, the multimedia data, | | | | Internet. Skype it is focused on the |
| interactive service. | | | | broad audience of users of the different |
| Commands(teams) of the report remind | | | | countries and interventions in work of a |
| HTTP, down to separate details. | | | | network with the purpose to forbid VoIP |
| Key feature SIP is client - server | | | | for him(it) are less terrible, because |
| opiented. Here it is meant, that at any | | | | it(he) is prepared for this. It is |
| network of a SIP-telephony there is a | | | | known, that report Skype has ability to |
| server (GateKeeper). | | | | find ways to transfer the voice |
| Report SIP is well focused for work in | | | | information. For example, if the |
| local networks and on good Internet - | | | | necessary range of ports of report UDP |
| channels. But what will take place when | | | | is closed (usually report Skype uses |
| the Internet - | | | | port UDP 40150), Skype is switched to |
| проваl | | | | use of free TCP-ports, down to obviously |
| 1;дер on what or the | | | | open 80 ports (HTTP), and if it is |
| reasons does not wish, that users could | | | | necessary, will use connection through |
| carry out bells through SIP? For | | | | HTTP-proxy. It means, that Skype will |
| achievement of the purpose to it "will | | | | work practically everywhere where |
| cut" enough UDP packages with value of | | | | Internet - sites "open". |
| port 5060 that SIP has ceased to work | | | | There are bases to consider, that Skype |
| normally. There are ways to avoid a | | | | uses the modified version of the |
| similar arbitrariness, however it | | | | standard SIP-report. In other words, SIP |
| intervention in work of the report | | | | was taken for a basis of report Skype |
| demand, forcing to forget about | | | | and it is modified, due to what Skype |
| compatibility with the standard | | | | has competitive before operators of a |
| equipment. | | | | SIP-telephony - cheapness support a |
| The report used Skype always was and | | | | user's network and ability to work |
| continues to remain closed from foreign | | | | almost everywhere and in any conditions. |
| developers. It has number of features | | | | |