1. Washington WASHINGTON UNIVERSITY IN ST LOUIS fredk@arl.wustl.edu Packet Routing Within MSR Fred Kuhns fredk@arl.wustl.edu

2. 2 Washington WASHINGTON UNIVERSITY IN ST LOUIS Fred Kuhns - 1/9/01 shim IP Header AAL5 Trailer IP Datagram Fragment offset VersionH-lengthTOSTotal length Identificationflags TTLprotocolHeader checksum Source Address Destination Address IP Options ?? IP data (transport header and transport data) AAL5 padding (0 - 40 bytes) CPCS-UU (0) Length (IP packet + LLC/SNAP) CRC Internal IP Packet Format 8 Bytes

3. 3 Washington WASHINGTON UNIVERSITY IN ST LOUIS Fred Kuhns - 1/9/01 IntraPort Shim Field Definitions Flags - Used by SPC to demultiplex incoming packets.The FPX sets flags to indicate reason for sending packet to SPC. Note, may also use flags to implement flow control. –AF: Active Flow –NR: No route in table –OP: IP Options present (Correct version but incorrect header size). –UK: Unknown packet type (incorrect version for example). Stream Identifier (SID): Flow ID for reserved traffic, locally unique label. FPX fills in for reserved flows. Input VIN - The physical port and sub-port packet arrived on. PN is the physical port number and SPI is the sub-port identifier corresponding to received VCI. FPX sets these values. Not clear that we need this in the IntraPort shim. Output VIN - output port and sub-port. The FPX sets this if the route lookup succeeds. If the SPC performs the lookup for the FPX then the SPC fills in. The SPC may also modify this value in order to re-route a packet - modifying seems dangerous, but setting ok. Output VIN Input VIN Stream Identifier Not Used Flags Virtual Interface Number Format PN (10 bits) SPI (6 bits) 01531 AFNROPUK X Flags

4. 4 Washington WASHINGTON UNIVERSITY IN ST LOUIS Fred Kuhns - 1/9/01 X Output VIN Not Used InterPort Shim Field Definitions Flags: TBD Input VIN - The physical port and sub-port packet arrived on. Filled in by Ingress FPX (or SPC if no FPX). PN is the physical port number and SPI is the sub-port identifier corresponding to received VCI. Output VIN - output port (PN, can be the VCI used to send packet to output port) and sub- port number which maps to the sending VCI. Input VIN Virtual Interface Number Format PN (10 bits) SPI (6 bits) 01531 Flags

5. 5 Washington WASHINGTON UNIVERSITY IN ST LOUIS Fred Kuhns - 1/9/01 FIPL Table Entry Formats Output VIN Stream Identifier A 0163135 Output VIN Stream Identifier 01631 FPX version of FIPL table entry (36 bits): TBD 15 SPC version of FIPL table entry (32 bits):

6. 6 Washington WASHINGTON UNIVERSITY IN ST LOUIS Fred Kuhns - 1/9/01 SPC FIPL IP eval plugins shim update shim demux Packet Routing Within MSR... 64... 127 (out port + 64) 63... 64... 127 (in port + 64) IngressEgress VCs to next hop routers (p2p conn) Ether only VC to endstations From previous hop router Ether only VC from endstations add shim rem shim FIPL shim proc. FPX SPC FIPL IP eval plugins shim demux shim update 63 Outbound VC = SPI + 128 0 <= SPI<= 15 Link Interface IP eval: IP processing for FPX. 1.Broadcast and Multicast destination address 2.IP options 3.Packet not recognized Inbound VC = SPI + 128 0 <= SPI <= 15 Currently Support at most 4 Inbound VCs: One for Ethernet or Four for ATM Current VCI Support: 1) 64 Ports (PN) 2) 16 sub-ports (SP)

7. 7 Washington WASHINGTON UNIVERSITY IN ST LOUIS Fred Kuhns - 1/9/01 Ingress SPC, No FPX interrupt PCU Framework Y.1 X.1Z.1 W.1 IP Options X.2Y.1 Z.2 SW Interrupt Priority HW Interrupt APIC Buffer Management Insert IntraPort Shim (Add Input VIN)... SP 1 SP 2 SP N APIC Exact Match (add SID) Route Lookup (Add Output VIN) SID? IP opt? Local Resource Manager (swint) APIC DQ Out PN 0 Out PN 1... Out PN M hi frequency interrupt (100us) CP commands CP command processor Command (AAL0) reply to CP Replace IntraShim with IntgerShim In/Out (AAL0) DQ Broadcast Cells

8. 8 Washington WASHINGTON UNIVERSITY IN ST LOUIS Fred Kuhns - 1/9/01 Egress SPC, No FPX interrupt PCU Framework Y.1 X.1Z.1 W.1 Manage X.2Y.1 Z.2 SW Interrupt Priority HW Interrupt APIC Buffer Management Insert IntraPort Shim (Add Input VIN)... SP 1 SP 2 SP N APIC Exact Match (add SID) SID? Local Resource Manager (swint) CP commands CP command processor Command (AAL0) reply to CP Determine Out VC Remove Shim APIC DQ Out PN 0 Out PN 1... Out PN M DRR Service drr thread hi frequency interrupt (100us) DQ Broadcast Cells

9. 9 Washington WASHINGTON UNIVERSITY IN ST LOUIS Fred Kuhns - 1/9/01 GigE Link Interface ARP Table (M Entries) MACIP IP 1 MAC 1 IP M MAC M... NH Table (4 entries) IPVC VC 1 IP 1 VC 4 IP 4... 65 = SP 1 66 = SP 2... 64+N = SP N to NH 64 = SP 0 to ES if VC != 64, Lookup VC in NH table returns IP used for ARP lookup (support N = 4) if VC = 64, Lookup IP destination address in packet header IP Header data AAL5 trailer IP Header data Ethernet Add Ethernet header using destination address from ARP table. Add our Ethernet source address. Maintain ARP table by snooping, sending ARPs and responding to ARP broadcasts. Software creates NH table at boot time. From FPX/SPC To Next Hop or Endstation

10. 10 Washington WASHINGTON UNIVERSITY IN ST LOUIS Fred Kuhns - 1/9/01 GigE Link Interface ARP Table (M Entries) MACIP IP 1 MAC 1 IP M MAC M... 64 = SP 0 to FPX/SPC IP Header data AAL5 trailer IP Header data Ethernet From Next Hop or Endstation To FPX/SPC If source MAC in table then verify else add If broadcast and ARP, process ARP else if broadcast and IP broadcast goto Deliver else if multicast and IP multicast goto Deliver else if not our destination MAC address drop else if IP unicast Deliver Remove Ethernet Header Encapsulate in AAL5 frame Send to switch on default VC (VC = 64)