]> Ericsson

No.5 Lize East street 100102 Beijing China harold.liu@ericsson.com

Ericsson

joel.halpern@ericsson.com

Ericsson

congjie.zhang@ericsson.com

General RFC Internet-Draft XML Extensible Markup Language RFC 5309 defines the Point-to-Point (P2P) circuit type, one of the two circuit types used in the link state routing protocols, and highlights that it is important to identify the correct circuit type when forming adjacencies, flooding link state database packets, and monitoring the link state. This document provides advice about the ifStack for the P2P interface over LAN ifType to facilitate operational control, maintenance and statistics.

defines the P2P circuit type and highlights that it is important to identify the correct circuit type when forming adjacencies, flooding link state database packets, and monitoring the link state. To simplify configuration and operational control, it is helpful to represent the fact that an interface is to be considered a P2P interface over LAN type explicitly in the interface stack. This enables, for example, routing protocols to automatically inherit the correct operating mode from the interface stack without further configuration (No need to explicitly configure the P2P interface in routing protocols). It is helpful to map the P2P interface over LAN type in the interface management stack table. If no entry specifies the P2P interface lower layer, management tools lose the ability to retrieve and measure properties specific to lower layers. The P2P interface over LAN type is intended to be used solely as a means to signal in standard network management protocols that make use of ifStackTables that the upper layer interface is P2P interface, and thus the upper and lower layers of P2P over LAN type will be expected to apply appropriate semantics: In general, P2P over LAN type higher layer SHOULD always be "ipForward" (Value 142, ), and the P2P over LAN type lower layer SHOULD be any appropriate link data layer of "ipForward". The assignment of 303, as the value for p2pOverLan ifType was made by Expert Review . So the purpose of this document is to request IANA to add this document as a reference to ifType 303, as well as suggest how to use ifStackTable for the P2P interface over LAN type, and provide examples. It should be noted that this document reflects the operating model used on some routers, others use different operating models may not represent a P2P as an ifIndex.

The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this document are to be interpreted as described in .

If a device implements the IF-MIB , each entry in the "/interfaces/interface" list (in "Interface Management YANG") in the operational state is typically mapped to one ifEntry as required in . Therefore the P2P interface over LAN type should also be fully mapped to one ifEntry by defining the "ifStackTable" ("higher-layer-if" and "lower-layer-if", defined in ). In ifStackTable the P2P interface over LAN type higher layer SHALL be network layer "ipForward" to enable IP routing, and the P2P interface over LAN type lower layer SHOULD be any link data layer that can be bound to "ipForward" including "ethernetCsmacd", "ieee8023adLag", "l2vlan", and so on (defined in IANA). The P2P interface over LAN type ifStackTable can be defined along the lines of following example (In the example, "lower-layer-if" takes "ethernetCsmacd" but in fact, "lower-layer-if" can be any other available link data layer. See for more examples) which complies with :

isis_int ianaift:ipForward eth1 ianaift:ethernetCsmacd p2p ianaift:p2pOverLan isis_int eth1 false down down 2021-04-01T03:00:00+00:00 ]]>

Because multiple IP interfaces can be bound to one physical port, the statistics on the physical port SHOULD be a complete set which includes statistics of all upper layer interfaces. Therefore, each p2p interface collects and displays traffic that has been sent to it via higher layers or received from it via lower layers.

P2P interface can be shutdown independently of the underlying interface. If P2P interface is administratively up, then the "oper-status", defined in , of the P2P interface SHALL fully reflect state of underlying interface; If the P2P interface is administratively down, the "oper-status" of the P2P interface SHALL be down. Details refer to .

The interface stack table specified in this document is read-only. Read operation to this table should not have a negative effect on network operations.

In the Interface Types registry, IANA has assigned a value of 303 for p2pOverLan with a reference of . IANA is requested to amend the reference for that code point to be to this document and to make a similar amendment in the YANG iana-if-type module (originally specified in ) which currently points to , as this document explains how the ifType is to be used.

The authors would like to thank Rob Wilton for his reviews and valuable comments and suggestions.

&RFC2119; &RFC2863; &RFC5309; &RFC7224; &RFC8174; &RFC8343; &RFC8561; &RFC6991;

In the case of underlying interface is VLAN sub-interface, the ifStackTable should be defined as:

isis_int ianaift:ipForward eth1_valn1 ianaift:l2vlan p2p ianaift:p2pOverLan isis_int eth1_valn1 false down down 2021-04-01T03:00:00+00:00 ]]>

In the case of underlying interface is LAG, the ifStackTable should be defined as:

isis_int ianaift:ipForward eth1_lag1 ianaift:ieee8023adLag p2p ianaift:p2pOverLan isis_int eth1_lag1 false down down 2021-04-01T03:00:00+00:00 ]]>

In the case of P2P interface and underlying interface are both administratively up, and the underlying interface operational status is up:

p2p ianaift:p2pOverLan isis_int eth1 up up ]]>

In the case of P2P interface and underlying interface are administratively up, but the underlying interface operational status is down:

p2p ianaift:p2pOverLan isis_int eth1 up down ]]>

In the case of P2P interface is administratively down:

p2p ianaift:p2pOverLan isis_int eth1 down down ]]>

In the case of P2P interface is administratively up but underlying is administratively down:

p2p ianaift:p2pOverLan isis_int eth1 up down ]]>