DHCP Server Service
6-8
6.3
DHCP Server Service
6.3.1
Synopsis
When acting as a router, the TCP/IP stack may also need to maintain the net-
work configuration on one of its network devices. A DHCP server allows the
stack to maintain the IP address of multiple Ethernet client devices. When
combined with Network Address Translation (NAT), the DHCP server can be
used to establish client membership in a private virtual network.
6.3.2
Operation
The DHCP server can be optionally configured to allocate IP addresses out
of a pool that is specified by an IP base address and the number of addresses
in the pool. If no pool is specified, the server will use static client entries in the
configuration system to resolve client address requests.
The sever will respond to DHCP requests from a single Ethernet device. This
allows for isolation of clients for a given interface, and allows multiple instances
of the DHCP server to manage different IP address pools for different inter-
faces.
6.3.3
DHCP Server Parameter Structure
The following structure defines the unique parameters of the DHCP server ser-
vice. It is located in the file: src\nettools\inc\dhcpsif.h.
//
// DHCPS Parameter Structure
//
typedef struct _ntparam_dhcps {
uint Flags; // DHCPS Execution Control Flags
IPN PoolBase; // First IP address in optional pool
uint PoolCount; // Number of addresses in optional pool
} NTPARAM_DHCPS;
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Flags – Execution control flags. Can be any combination of the following:
J
DHCPS_FLG_LOCALDNS – Causes DHCPS to report its own IP ad-
dress as the local DNS server to clients. If this flag is not set, DHCPS
reports the DNS servers as contained in the “SYSINFO” portion of the
configuration.
J
DHCPS_FLG_LOCALDOMAIN – Causes DHCPS to report the local
domain name assigned to the virtual network to clients. If this flag is
not set, DHCPS reports the public domain name to clients.
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PoolBase – The first IP address (in network format) of the address pool