User's Manual

hwc_apstartup.fm
Configuring the Wireless AP
Discovery and registration overview
A31003-W1050-U100-2-7619,
March 2008
HiPath Wireless Controller, Access Points and Convergence Software V5 R1 , C20/C2400 User Guide 73
• SLP (Service Location Protocol) – A means of allowing client
applications to discover network services without knowing their location
beforehand. Devices advertise their services using a Service Agent (SA).
In larger installations, a Directory Agent (DA) collects information from
SAs and creates a central repository (SLP RFC2608).
The HiPath Wireless Controller contains an SLP SA that, when started,
queries the DHCP server for Option 78 and if found, registers itself with the
DA as service type Siemens. The HiPath Wireless Controller contains a DA
(SLPD).
The Wireless AP queries DHCP servers for Option 78 in order to locate any
DAs. The Wireless APs SLP User Agent then queries the DAs for a list of
Siemens SAs.
Option 78 must be set for the subnets connected to the ports of the HiPath
Wireless Controller and the subnets connected to the Wireless APs. These
subnets must contain an identical list of DA IP addresses.
• Step 4 – Use a Domain Name Server (DNS) lookup for the host name
Controller.domain-name.
If no DA is found, or if it has no Siemens SAs registered, the Wireless AP
attempts to locate a HiPath Wireless Controller via DNS.
If you use this method for discovery, place an A record in the DNS server for
Controller.<domain-name>. The <domain-name> is optional, but if used,
ensure it is listed with the DHCP server.
• Step 5 – Use a multicast SLP request to find SLP SAs
If all of the preceding methods fail to locate a HiPath Wireless Controller, the
Wireless AP sends a multicast SLP request, looking for any SLP Service
Agents providing the Siemens service.
4.2.2 Registration after discovery
Any of the discovery steps 2 through 5 can inform the Wireless AP of a list of
multiple IP addresses to which the Wireless AP may attempt to connect. Once the
Wireless AP has discovered these addresses, it sends out connection requests
to each of them. These requests are sent simultaneously. The Wireless AP will
attempt to register only with the first which responds to its request.
When the Wireless AP obtains the IP address of the HiPath Wireless Controller,
it connects and registers, sending its serial number identifier to the HiPath
Wireless Controller, and receiving from the HiPath Wireless Controller a port IP
address and binding key.