User's Manual

Chapter 4 Broadband
B222s User’s Guide
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2 The AP sends out a discovery request , looking for an AP in CAPWAP AP cont roller m ode.
3 I f t here is an AP controller on t he net work, it receives t he discovery request. I f t he AP controller is
in Ma nual m ode it adds t he details of t he AP to it s Un m a nage d Acce ss Point s list , and you
decide which available APs t o m anage. I f t he AP is in Alw a ys Acce pt m ode, it aut om at ically adds
the AP t o its M a nage d Acce ss Point s list and provides the m anaged AP wit h default configuration
inform ation, as well as securely transm itt ing the DTLS pre- shared key. The m anaged AP is ready for
association wit h wireless clients.
Managed AP Finds the Controller
A m anaged LTE Device can find t he cont roller in one of the following ways:
• Manually specify t he controller ’s I P address using t he com m ands. See t he LTE Device CLI
Reference Guide for details.
• Get the cont roller’s I P address from a DHCP server wit h t he controller ’s I P address configured as
option 138.
• Broadcast ing t o discover t he controller wit hin t he broadcast dom ain.
The AP controller m ust have a st at ic I P address; it cannot be a DHCP client .
CAPWAP and IP Subnets
By default, CAPWAP works only bet ween devices wit h I P addresses in the sam e subnet ( see the
appendices for inform at ion on I P addresses and subnet t ing) .
However, you can configure CAPWAP t o operat e between devices wit h I P addresses in different
subnet s by doing t he following.
• Activat e DHCP. Your net work’s DHCP server m ust support opt ion 138 defined in RFC 5415.
• Configure DHCP opt ion 138 wit h t he I P address of the CAPWAP AP cont roller on your network.