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CAPWAP WG. CAPWAP Tunneling Protocol (CTP) draft-singh-capwap-ctp-02.txt Inderpreet Singh, Chantry Networks Inc. IETF 63, Paris, France. CTP docs. Protocol Draft http://www.ietf.org/internet-drafts/draft-singh-capwap-ctp-02.txt Self Evaluation Draft
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CAPWAP WG CAPWAP Tunneling Protocol (CTP) draft-singh-capwap-ctp-02.txt Inderpreet Singh, Chantry Networks Inc. IETF 63, Paris, France
CTP docs • Protocol Draft • http://www.ietf.org/internet-drafts/draft-singh-capwap-ctp-02.txt • Self Evaluation Draft • http://www.ietf.org/internet-drafts/draft-francisco-capwap-ctp-evaluation-01.txt
Base Functionality of CTP • AP to AC Registration Functions • Exchange of security credentials • Authentication mechanisms • Capability exchange (Split/Local MAC) • AP and AC session creation • Connection State Management • Periodic poll messages to confirm connectivity between AP and AC • Supports availability failover and alert triggers
Base Functionality of CTP • Mobile Session Management • Connection management • MU connection and disconnection services • MU Authentication and Key management • Policy exchange services • Encapsulation of User Data • Encapsulated 802.3 data • Data can be tunneled to AC (split/local MAC) or bridged locally by AP (local MAC) • Identifiers that assist in understanding policy assignment (i.e. Network ID, AP ID etc.) • Preservation of QoS (TOS bit translation)
Base Functionality of CTP • AP Management • AP State Management • Security association, reset services, operational state • Configuration • AP auto request on boot up • Triggered from AC • Statistics • Periodic polling from AC • Firmware Upgrade Triggers • AP auto request on boot up • Triggered from AC
Control, management and provisioning of WTPs and ACs Radio technology agnostic Flexibility to address CAPWAP architectures (Local and Split MAC) The Original CTP Objectives
CTP Transport • UDP based • Encryption above UDP • No distinction of L2 or L3 • No fragmentation/reassembly in protocol because of IP • No L2 specific discovery mechanisms • Note: implementation uses interoperable standard discovery methods (SLP, DNS,…)
Configuration and Statistics • Assumption: All WTPs incorporate an SNMP agent • This is true for 802.11 Access Point reference designs, but also assumed for future wireless APs • Every 802 standard has a MIB defined • Example: 802.11 Annex D defines 802.11 MIB already • Configure and statistics payload encoded in ASN.1; use CTP for transport • Advantages: • Need to do MIB work anyway for CAPWAP • Flexible and modular for other wireless technologies • Don’t have to change the protocol to parallel new amendments to wireless MAC technologies
Refined Capabilities Exchange • Message CTP-Cap-Req • Attributes • ATT-NUM-RADIOS • ATT-RADIO-INFO • Radio-Index • Phy-Type • Num-Networks • ATT-MAC-INFO • Radio-Index • MAC-CAP • AUTH-CAP • ENCRYPT-CAP • ATT-NETWORK-INFO • ATT-VENDOR-ID • ATT-PRODUCT-ID • Message CTP-Cap-Rsp • Attributes • ATT-RADIO-INFO-ACK • Radio-Index • CAP-ACK
Local vs. Split (AP) Local vs Split interoperation: model negotiated during cap. exchange +--+--+ +----+------+ Control <===>| | | | | CTP |<===========>|WirelessMAC| Tunnel Data <--->| | | | +--+--+ +----+------+ ^ ^ | +-----------+ | | | | | Data (optional) <-------+--->| L2 bridge |<---+ | | +-----------+ Local +--+--+ +----+------+ Control <===>| | | | MAC Management <===>| CTP |<===========>| Wireless | Tunnel Data <--->| | |MAC Control| +--+--+ +----+------+ ^ ^ | +-----------+ | (Optional) | | | | Data <------------+--->| L2 bridge |<---+ | | +-----------+ Split*
New Data format • -02 has CTP-Data type change • If bit X is set then message payload contains 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + RSSI | RATE | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ • This is to accommodate local and split MAC.
Next Steps • Identify and clean inconsistencies • Incorporate any comments from evaluation, if any • Add minimum set of OIDs to enable configuration of CAPWAP functions that are non-radio or non-wireless MAC related • Fix typos