1. IPv4 over 802.16 IP CS draft-madanapalli-16ng-ipv4-over-802-dot-16-ipcs-00 Soohong Daniel Park Syam Madanapalli 68 – Prague, Czech Republic March 18-23, 2007

2. Objective Introduce the draft Introduce the draft Summarize discussion on mailing list Summarize discussion on mailing list Solicit feedback from WG Solicit feedback from WG Way forward Way forward Adopt as a WG draft? Adopt as a WG draft?

3. IPv4 Convergence Sublayer IPv4 CS is responsible for the transmission and reception of IPv4 packets Functions of IPv4 CS Classification of an IPv4 packet to an appropriate MAC Connection Payload Header Suppression (PHS) (optional) Delivery of the resulting IPv4 CS PDU to the MAC-CPS SAP to deliver to the peer MAC-CPS SAP. Receipt of the IPv4 CS PDU from the MAC-CS SAP Rebuilding the IPv4 header if PHS is in use Classification parameters constitute of IPv4 Header and Transport Header Source and Destination IPv4 addresses Source and Destinations Ports Type-of-Service IP Protocol Filed 802.16 MAC CPS 802.16 IPv4 CS ULP IPv4

4. Network Architecture MS and AR are on point-to-point link 802.16 MAC connection between MS and BS L2 tunnel between BS and AR Point-to-point IP link MS 1 AR MS 2 BS 1 MS 3 MS 4 BS 2 ToInternet

5. Frame Format 0 1 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |H|E| Type |R|C|EKS|R|LEN | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | LEN LSB | CID MSB | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | CID LSB | HCS | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | IPv4 | +- header -+ | | +- and -+ / payload... / +- -+ | | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |CRC (optional) | +-+-+-+-+-+-+-+-+

6. Maximum Transmission Unit (MTU) 802.16 Frame has 11 bits for frame length 802.16 Frame has 11 bits for frame length It supports MTU of 2^11 – 10 (MAC Header + CRC) = 2038 Octets It supports MTU of 2^11 – 10 (MAC Header + CRC) = 2038 Octets IPv4 MTU IPv4 MTU Default MTU – 1500 octets Default MTU – 1500 octets Minimum MTU 576 octets Minimum MTU 576 octets maximum MTU 2038 octets maximum MTU 2038 octets

7. Address Assignment Each MS is assigned an unique IPv4 address using DHCP Each MS is assigned an unique IPv4 address using DHCP DHCP is run over initial MAC transport connection DHCP is run over initial MAC transport connection AR shall implement either DHCP Server or DHCP relay to forward the DHCP request to the DHCP server AR shall implement either DHCP Server or DHCP relay to forward the DHCP request to the DHCP server Mailing list Discussion: Mailing list Discussion: Should we recommend a subnet model for address Assignment? Should we recommend a subnet model for address Assignment? Can we recommend RFC 3021 (Using 31-Bit Prefixes on IPv4 Point-to-Point Links)? Can we recommend RFC 3021 (Using 31-Bit Prefixes on IPv4 Point-to-Point Links)?

8. Address Resolution Protocol (ARP) ARP is not required for IPv4 CS, as MAC address is not used for data path ARP is not required for IPv4 CS, as MAC address is not used for data path Mailing list discussion Mailing list discussion ARP packets must not be transmitted over the air for IPv4 CS ARP packets must not be transmitted over the air for IPv4 CS ARP does not have the IPv4 header so the ARP packets cannot be mapped onto 802.16 MAC connection ARP does not have the IPv4 header so the ARP packets cannot be mapped onto 802.16 MAC connection Solution for legacy IPv4 Stack Solution for legacy IPv4 Stack A shim layer between the IPv4 stack and the 802.16 IPCS layer at the MS to filter ARP requests arriving from the IPv4 stack and respond with any MAC address A shim layer between the IPv4 stack and the 802.16 IPCS layer at the MS to filter ARP requests arriving from the IPv4 stack and respond with any MAC address However this is an implementation issue However this is an implementation issue

9. Multicast Address Mapping Mapping of multicast IP address to MAC address Mapping of multicast IP address to MAC address 802.16 MAC address is not used for the data path 802.16 MAC address is not used for the data path Instead it uses the Connection ID (CID) Instead it uses the Connection ID (CID) Hence no mapping is required Hence no mapping is required

10. Way Forward Adopt as a WG draft? Adopt as a WG draft?