BGP: Difference between revisions

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= MED vs Local Preference =
= MED vs Local Preference =
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;Multi-Exit Discriminator
*The MED is an optional attribute that comes in handy when there are multiple entrance paths to an AS.
*The MED is an optional attribute that comes in handy when there are multiple entrance paths to an AS.
*The remote AS sets MED values to tell the other AS which path to use.
*The remote AS sets MED values to tell the other AS which path to use.
*The MED is passed between the two autonomous systems, but the value is not passed to any other ASes.
*The MED is passed between the two autonomous systems, but the value is not passed to any other ASs.
*The path with the lowest MED is the preferred path.
*The path with the lowest MED is the preferred path.
*This attribute is only used to influence entry INTO the AS.
*This attribute is only used to influence entry INTO the AS.


;Local Preference

*LOCAL_PREF is a well-known attribute that is also used when multiple paths between autonomous systems exist.
*LOCAL_PREF is a well-known attribute that is also used when multiple paths between autonomous systems exist.
*The LOCAL_PREF attribute is just that… local and exclusive to the AS.
*The LOCAL_PREF attribute is just that… local and exclusive to the AS.