Configuring flow control negotiation of X.25 switching
Figure 127: X.25 switching
![](images/image123.png)
As shown in Figure 127, Router A and Router C communicate through Router B. You can enable or disable on Router B flow control negotiation between Router A and Router C.
With flow control negotiation enabled between the two ends, if the flow control parameters on the connecting links at the two ends of Router B are inconsistent, the two ends negotiate to use the smaller parameters. Then, when Router B receives packets with M-bit 1, which indicates that subsequent fragments exist, Router B forwards the packets directly without processing them.
With flow control negotiation disabled between the two ends, the flow control parameters of the links at the two ends of Router B can be different. When Router B receives packets with M-bit 1, it reassembles the fragments and then forwards the assembled packets instead of forwarding the fragments directly. When Router B forwards packets to Router C, Router B might refragment the packets depending on the flow control parameters of the link between Router B and Router C.
By default, flow control negotiation is enabled for X.25 switching.
To configure flow control negotiation on an X.25 interface:
Step | Command | Remarks |
---|---|---|
1. Enter system view. | system-view | N/A |
2. Enter interface view. | interface interface-type interface-number | N/A |
3. Enable flow control negotiation for X.25 switching. | x25 flowcontrol | Enabled by default. |