Method and device for controlling routing oscillation

Abstract

The invention discloses a method and a device for controlling route oscillations and belongs to the communications field. The method comprises the following steps: when the initial change of a route takes place, timing begins and the changing degree of the route is recorded; when the changing degree reaches a preset degree threshold, the route is restrained; and when the duration of preset time is reached, and the recorded changing degree is equal to or larger than a preset path quest threshold, the restraint of the route is removed. The device comprises a timing module, a changing degree recording module, a restraining module and a restraint removing module. The device starts timing and restrains the route when the route begins to oscillate, judges the state of the route according to the oscillation degree of the route in the duration of the preset time, removes the restraint on the route which is in a quest state, prevents the problem of slow convergence of the route caused by a wrong restraint on the route oscillations, and can restrain the route which really oscillates.

Description

technical field [0001] The invention relates to the communication field, in particular to a method and equipment for controlling route oscillation. Background technique [0002] The intermittent appearance and disappearance of a route is called route flapping. Network link failures, network maintenance, and network misconfigurations can cause some routes to flap. When a new route appears, the router will send an update (update) message to the neighbor; when a new route disappears, the router will send a withdrawal (withdraw) message to the neighbor; route flapping will cause the router to periodically spread in the Internet A large number of update or withdrawal messages. These update or withdraw messages consume link bandwidth and increase the load on the router's CPU. [0003] The prior art provides a method for BGP (Border Gateway Protocol, Border Gateway Protocol) to suppress route flapping. This method sets a penalty value (Penalty) for each route. When a certain rout...

AI Technical Summary

Problems solved by technology

If the flapping frequency of a route is very low, the cumulative penalty value corresponding to the route is very small, and the penalty value of the route can be reduced to the reuse threshold reuse-1imit in a short period of time. This method cannot be used for routes with a low flapping frequency. inhibition

[0006] 2) This method does not find the route that really causes network shocks. For example, in the Internet, if multiple routes pass through a certain public link, when this link fails, these routes will all fail

However, under normal circumstances, due to the difference in the processing speed of routers and the propagation speed of the network, the withdrawal messages for these routes will arrive at the same router at different times, causing this router to select the route that is actually invalid as the best route. , and advertise the new best route, however, the withdrawal message for this new best route will soon reach the router, causing the router to send a withdrawal message to the best route just announced, resulting in a short-term There will be a large number of route withdrawal messages in the network. When all the route withdrawal messages for the public link arrive, the route convergence is complete and no oscillation will occur again. The above process is called path hunting (path hunting or path exploration)

Path exploration will cause a route to change at a very high frequency in a short period of time, and the corresponding penalty value is very large. Through the above method of suppressing route oscillation, this type of route will be suppressed, and the suppression time is very long, about 15 Minutes, causing the routing convergence speed to slow down

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