Strict routing and loose routing in the SIP protocol

Strict routing and loose Routing

1. The address list of a loose route does not list a complete and strict path, but only provides some key points in the path..You can use the automatic route selection function of the vro to route data between key points. data packets must also be copied during data packet sharding.

In a SIP message, if the parameter in the first Route Header field contains the LR parameter, It is a loose route.

2. Strict routing requirements data packets must pass through each vro in strict accordance with the path specified by the sender. These vrouters should be connected one by one. No other unspecified vro can be found between each two specified vrouters,And the router order is notChange

Changed.If a data packet cannot directly reach the vro specified in the next hop during transmission, the vro will discard the data packet and generate an unattainable ICMP error message for the source route failure to be reported to the sender.

In a SIP message, if the parameter in the first Route Header does not contain the LR parameter, It is a strict route.

Strict routing and loose Routing

The proxy must process the request according to the following steps:

1. Whether it is a loose route or a strict route,

-If the value of the first Route Header field matches its Uri, delete the value of the first Route Header field.

2. If it is a strict route,

-The request-URI must be placed in the last value in the route header field.

-You must put the value of the first Route Header field in request-Uri and delete it from the route header field.