User's Manual
Table Of Contents
- Welcome to the Airespace Product Guide!
- OVERVIEWS
- About the Airespace System
- About the AireOS
- Single-Airespace Switch or Appliance Deployments
- Multiple-Airespace Switch and Appliance Deployments
- About AireOS Security
- About Airespace Wired Security
- About AireWave Director Software
- About the Master Airespace Switch or Appliance
- About the Primary Airespace Switch or Appliance
- About Client Roaming
- About External DHCP Servers
- About Airespace Mobility Groups
- About Airespace Wired Connections
- About Airespace WLANs
- About File Transfers
- About Power Over Ethernet
- About Airespace Switches and Appliances
- 4012 and 4024 Airespace Wireless Switch Models
- 4101 and 4102 Airespace WLAN Appliance Models
- Airespace Switch and Appliance Features
- Airespace Switch and Appliance Model Numbers
- Airespace Wireless Switch Direct Connect Mode
- Airespace Switches and Appliances in Appliance Mode
- Airespace Wireless Switch Hybrid Mode
- About the Distribution System Port
- About the Service (Management) Port
- About the Startup Wizard
- About Airespace Switch and Appliance Memory
- Airespace Switch and Appliance Failover Protection
- Switched Network Connection to the Airespace Switch or Appliance
- Enhanced Security Module
- About Airespace Access Points
- About Airespace AP Models
- About Airespace AP External and Internal Antennas
- About Airespace AP LEDs
- About Airespace AP Connectors
- About Airespace AP Power Requirements
- About Airespace AP External Power Converter
- About Airespace AP Mounting Options
- About Airespace AP Physical Security
- About Airespace AP Monitor Mode
- About Third-Party Access Points
- About Rogue Access Points
- About the Airespace Control System Software
- About the Airespace Web Browser Interface
- About the Airespace Command Line Interface
- About the Airespace System
- SOLUTIONS
10/10/03 External DHCP Servers
90-100584-004 Airespace Product Guide 16
About External DHCP ServersExtern al DHCP Se rvers
The AireOS is designed to operate as a ‘DHCP Proxy’ with industry-standard external DHCP Servers that
support DHCP Relay. This means that each Airespace Wireless Switch or WLAN Appliance appears as a
DHCP Relay agent to the DHCP Server. This also means that the Airespace Switch or Appliance appears
as a DHCP Server to wireless clients at the virtual IP address.
Because the Airespace Switch or Appliance controls the client IP address obtained from a DHCP Server,
it maintains the same IP address for that client during same-Airespace Switch or Appliance,
inter-Airespace Switch and Appliance, and inter-subnet Client Roaming
.
Per-WLAN AssignmentPer-WLAN Assignment
All Airespace WLANs can be configured to use the same or different DHCP Servers, or no DHCP Server.
This allows operators considerable flexibility in configuring their Wireless LANs, as further described in
the Airespace WLANs
section.
Note that Airespace WLANs that support Management over Wireless must allow the management
clients to obtain an IP address from a DHCP Server.
Security ConsiderationsSecurity Considera tions
For enhanced security, it is recommended that operators require all clients to obtain their IP addresses
from a DHCP server. To enforce this requirement, all Airespace WLANs can be configured with a ‘DHCP
Required’ setting and a valid DHCP Server IP address, which disallows client static IP addresses. If a
client associating with a WLAN with ‘DHCP Required’ set does not obtain its IP address from the desig-
nated DHCP Server, it is not allowed access to any network services.
If slightly less security is tolerable, operators can create Airespace WLANs
with ‘DHCP Required’
disabled and a valid DHCP Server IP address. Clients then have the option of using a static IP address
or obtaining an IP address from the designated DHCP Server.
Operators are also allowed to create separate Airespace WLANs with ‘DHCP Required’ disabled and a
DHCP Server IP address of 0.0.0.0. These WLANs drop all DHCP requests and force clients to use a
static IP address. Note that these WLANs do not support Management over Wireless
.