Interface Configuration
7750 SR OS Interface Configuration Guide
Page 33
Figure 1: MLPPP 24-bit Fragment Format
Figure 2: MLPPP 12-bit Fragment Format
The required and default format for MP is the 24-bit format. During the LCP state the 12-bit
format can be negotiated. The SR-series routers should be capable of supporting and negotiating
the alternate 12-bit frame format.
Protocol Field (PID)
The protocol field is two octets its value identifies the datagram encapsulated in the Information
field of the packet. In the case of MP the PID also identifies the presence of a 4-octet MP header
(or 2-octet, if negotiated).
A PID of Ox003d identifies the packet as MP data with an MP header.
The LCP packets and protocol states of the MLPPP session follow those defined by PPP in RFC
1661. The options used during the LCP state for creating an MLPPP NCP session are described
below.
B & E Bits
The B&E bits are used to indicate the epoch of a packet. Ingress packets to the MLPPP process
will have an MTU, which may or may not be larger than the MRRU of the MLPPP network. The
B&E bits manage the fragmentation of ingress packets when it exceeds the MRRU.
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Содержание 7750 SR OS
Страница 6: ...Page 6 7750 SR OS Interface Configuration Guide Table of Contents ...
Страница 8: ...Page 8 7750 SR OS Interface Configuration Guide List of Tables ...
Страница 10: ...Page 10 7750 SR OS Interface Configuration Guide List of Figures ...
Страница 14: ...Preface Page 14 7750 SR OS Interface Configuration Guide ...
Страница 16: ...Getting Started Page 16 7750 SR OS Interface Configuration Guide ...
Страница 184: ...Card MDA and Port Command Reference Page 184 7750 SR OS Interface Configuration Guide ...
Страница 417: ...Interface Configuration 7750 SR OS Interface Configuration Guide Page 417 4 5 SAP PVT 1 1 up up A ima2 ...
Страница 429: ...Interface Configuration 7750 SR OS Interface Configuration Guide Page 429 Cells 0 0 Unknown VPI VCI Cells 0 A ALA 49 ...
Страница 437: ...Interface Configuration 7750 SR OS Interface Configuration Guide Page 437 bundle num 1 256 type ppp ...
Страница 438: ...Debug Commands Page 438 7750 SR OS Interface Configuration Guide ...
Страница 444: ...Index Page 444 7750 SR OS Interface Configuration ...