Icps

Source: https://slideplayer.
com/slide/3428428/
 ICMP
 ARP
 RARP
 DHCP
Source: https://slideplayer.com/slide/3428428/
 The IP (Internet Protocol) relies on several
other protocols to perform necessary control
and routing functions:
 Control functions (ICMP)

 Multicast signaling (IGMP)
 The Internet Control Message Protocol (ICMP)
is a helper protocol that supports IP with
facility for
◦ Error reporting
◦ Simple queries
 ICMP messages are encapsulated as IP datagrams:
IP header ICMP message
IP payload
ICMP query:
 Request sent by host to a router or host
 Reply sent back to querying host
Type/Code: Description
8/0 Echo Request The ping command

uses Echo Request/
0/0 Echo Reply Echo Reply
 Ping’s are handled directly by the kernel
 Each Ping is translated into an ICMP Echo
Request
 The Ping’ed host responds with an ICMP Echo
Reply
Host Host
or or
Router router
 ICMP error messages report error conditions
 Typically sent when a datagram is discarded
 Error message is often passed from ICMP to
the application program
 RFC 792: If, in the destination host, the IP module cannot deliver the datagram because the indicated
protocol module or process port is not active, the destination host may
send a destination unreachable message to the source host.
 Scenario:
No process
is waiting
at port 80
Client Server
TCP UDP Transport
Layer
ICMP IP IGMP Network

Layer
Network
ARP Access
RARP Link Layer
Media
 Note:
◦ The Internet is based on IP addresses
◦ Data link protocols (Ethernet, FDDI, ATM) may have
different (MAC) addresses
 The ARP and RARP protocols perform the
translation between IP addresses and MAC layer
addresses
ARP Ethernet MAC

IP address
address
(32 bit)
(48 bit)
RARP
ARP Request:
Argon broadcasts an ARP request to all
stations on the network: “What is the
hardware address of Router137?”
Argon Router137
128.143.137.144 128.143.137.1
00:a0:24:71:e4:44 00:e0:f9:23:a8:20
ARP Request:
What is the MAC address
of 128.143.71.1?
ARP Reply:
Router 137 responds with an ARP Reply which
contains the hardware address
Argon Router137
128.143.137.144 128.143.137.1
00:a0:24:71:e4:44 00:e0:f9:23:a8:20
ARP Reply:
The MAC address of 128.143.71.1
is 00:e0:f9:23:a8:20
 Dynamic assignment of IP addresses is
desirable for several reasons:
◦ IP addresses are assigned on-demand
◦ Avoid manual IP configuration
◦ Support mobility of laptops
 Three Protocols:
◦ RARP (until 1985, no longer used)
◦ BOOTP (1985-1993)
◦ DHCP (since 1993)
 Only DHCP is widely used today.
 Dynamic Host Configuration Protocol (DHCP)
◦ Designed in 1993
◦ An extension of BOOTP (Many similarities to BOOTP)
◦ Same port numbers as BOOTP
◦ Extensions:
 Supports temporary allocation (“leases”) of IP
addresses
 DHCP client can acquire all IP configuration parameters
◦ DHCP is the preferred mechanism for dynamic

assignment of IP addresses
◦ DHCP can interoperate with BOOTP clients.
Argon
128.143.137.144
00:a0:24:71:e4:44 DHCP Server
DHCP Response:
IP address: 128.143.137.144
Default gateway: 128.143.137.1
Netmask: 255.255.0.0
DHCP Client
DHCPDISCOVER
DCHP DISCOVER
Sent to 255.255.255.255

DHCP Server
DHCP Client
00:a0:24:71:e4:44 DHCPOFFER DHCP Server
DCHP OFFER
DHCPOFFER

DHCP Server
DHCP Client
DHCPREQUEST
 DCHP REQUEST DHCPACK
At this time, the DHCP DHCP Server
client can start to use

the IP address DHCP Client
DHCPREQUEST
DHCPACK
 Renewing a Lease
(sent when 50% of lease
has expired)
DHCP Server
If DHCP server sends
DHCPNACK, then
address is released.
DHCP Client
 DCHP RELEASE DHCPRELEASE
At this time, the DHCP

client has released the IP
address DHCP Server
IGMP is a protocol that manages group
membership. The IGMP protocol gives the
multicast routers information about the
membership status of hosts (routers) connected
to the network.
A multicast router connected to a network has a
list of multicast addresses of the groups with at
least one loyal member in that network. For
each group, there is one router that has the duty
of distributing the multicast packets destined
for that group.

Icps

Uploaded by

Copyright:

Available Formats

Icps

Uploaded by

Document Information

Original Title

Copyright

Available Formats

Share this document

Share or Embed Document

Sharing Options

Did you find this document useful?

Is this content inappropriate?

Copyright:

Available Formats

Icps

Uploaded by

Copyright:

Available Formats

Source: https://slideplayer.

 Control functions (ICMP)

 ICMP messages are encapsulated as IP datagrams:

IP header ICMP message

8/0 Echo Request The ping command

ICMP IP IGMP Network

ARP Ethernet MAC

◦ DHCP is the preferred mechanism for dynamic

 DCHP REQUEST DHCPACK

At this time, the DHCP DHCP Server

client can start to use

 DCHP RELEASE DHCPRELEASE

At this time, the DHCP

You might also like