Mlppp; Lcp Options; Mlppp Header - HP ProCurve Secure Router 7203 dl Advanced Management And Configuration Manual

MLPPP

MLPPP establishes a session between two peers using the same protocols and
phases as typical PPP. However, MLPPP adds:
three option fields to the LCP frames
an MLPPP header to the information field of the PPP frame

LCP Options

The receiving peer must know that the sending peer will be fragmenting PPP
frames and transmitting them over multiple carrier lines. The receiving peer
must also be able to recognize that these fragmented frames originate from a
single peer. Three LCP options prepare peers to exchange PPP frames over
an MLPPP connection:
Maximum Receive Reconstructed Unit (MRRU)—The MRRU option
serves two functions: it indicates that the sending peer wants to, and that
the receiving peer can, use MLPPP, and it specifies the size of the recon-
structed frame (replacing the MRU).
Short Sequence Number Header Format—A peer can request to use a 12-
bit rather than a 24-bit sequence number in the MLPPP header. A 12-bit
sequence number enables a frame to be split into a little less than 5,000
fragments, which is more than adequate for the typical bundle of lines.
Endpoint Discriminator (ED) options—Peers negotiate how the receiving
peer will identify the sending peer. One of these methods is an ED, which
can be generated from an IP address, media access control (MAC)
address, or PPP magic number. Every carrier line in the MLPPP bundle
originates from the same endpoint and is given the same ED. The receiving
peer recognizes that frames received from different carrier lines, but with
the same ED, come from the same peer.

MLPPP Header

The MLPPP header helps the receiving peer reconstruct frame fragments in
the correct order. When a peer sends a PPP frame across a multilink point-to-
point connection, it first fragments the PPP frame. It then encapsulates
fragments in new PPP frames and sends them simultaneously over each
aggregated line. The new PPP frame includes:
a new PPP header
a four-field MLPPP header
a fragment of the original PPP frame
Increasing Bandwidth
Configuring MLPPP
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