Redirect to a specific LSP used by a VPRN service

The router supports traffic steering within a VPRN, enabling the transport tunnels used by the SDP to be used for specific flows redirected from the system-selected default. This redirection enables large bandwidth flows to be moved to an alternative LSP.

For matching ingress traffic on a VPRN, the switch-defined-cookie command must be enabled, with the cookie encoded to match the ingress VPRN’s service ID.

Traffic can be redirected to the following:

Parameters must be matched in the OF encoding to steer traffic.

flow_mod:
instruction type: OFPIT_WRITE_ACTIONS/OFPIT_APPLY_ACTION, 
Action 1:
action type: OFPAT_EXPERIMENTER
ALU_IPD_EXPERIMENTER_ID:  0x000025BA
ExpType= ALU_AXN_REDIRECT_TO_NEXTHOP,
Action 2:
action type: OFPAT_OUTPUT, 

port= SR OS LOGICAL port encoding RSVP-TE, MPLS-TP LSP, or segment routing, as described in SR OS H-OFS logical port section.

Action 3 (optional): to redirect to a different VPRN

Action 3:
action type: OFPAT_EXPERIMENTER
ALU_IPD_EXPERIMENTER_ID:  0x000025BA
ExpType= ALU_AXN_REDIRECT_TO_VPRN,

Encoding:

struct alu_axn_redirect_to_vprn {
    uint16_t              type;                   /* OFPAT_EXPERIMENTER =>  ff ff */
    uint16_t              len;
    uint32_t              experimenter;           /
* Vendor specific experimenter id => 00 00 25 ba */
    uint8_t               exp_axn_type;          /*  type => 03 */
    uint8_t               exp_axn_flags;         /* flag => any value is accepted */
    uint8_t               pad[2];                /* pad => 00 00  */         
    uint32_t              vprn;                  /* vrpn svc id */
};ASSERT(sizeof(alu_axn_redirect_to_vprn) == 16)

Action 4 (optional): to redirect to a different prefix

Action 4:
action type: OFPAT_SET_FIELD

Field is an IP destination address. Subnet masks are not supported in the set_field instruction.