Transcript More TCP/IP Protocols - York Technical College

More TCP/IP Protocols
Chapter 6 Lecture 2
HTTP
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Hypertext Transfer Protocol
Allows text, graphics, multimedia to be
downloaded from an web server
HTTP clients = web browsers
Uses UDP
URL – uniform resource locator
HTML – scripting language for web
pages
HTTPS
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Hypertext Transfer Protocol Secure
Employs secure socket layers
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SSL – an added protocol layer between HTTP and
the Transport layer
Encrypts information transmitted between clients
(Netscape and Microsoft) and web servers.
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Web servers
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Apache
Microsoft IIS
Telnet
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Terminal emulator
Sessions opened on a remote host
Allows user to access applications and
data on the host computer. Use the
host for processing.
Authentication required
Uses TCP.
ICMP
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Internet Control Message Protocol
Message control and error reporting
between host and server
Works with IP
Tracert and Ping are two of the most
commonly used ICMP network
management tools.
ARP
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Address Resolution Protocol
Allows a device that knows a
destination’s IP address but doesn’t
know the destination’s MAC address to
find it.
NTP
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Network Time Protocol
Synchronize computer clock times of all
computers in the LAN.
Network Services
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DHCP/BOOTP
DNS
NAT/ICS
WINS
SNMP
DHCP
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Dynamic Host Configuration Protocol
A server is set up with this service to
dynamically assign IP addresses to hosts.
Scope – the range of IP addresses from
which the DHCP server assigns addresses
Lease – the amount of time which the server
assigns IP address to the host
Reservation – an IP address is reserved for a
particular host
Not platform dependent
DHCP Advantages &
Disadvantages
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Eliminates manual configuration for each host
Eliminates duplicate IP addresses (human
error)
Eliminates need to reconfigure if the host is
moved
Increases traffic (disadvantage)
DHCP server must be installed and
configured. (disadvantage)
BOOTP
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Older protocol to automatically assign
IP addresses to hosts.
DHCP was modeled after BOOTP.
DNS
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Domain Name Service
Requires a server configured as a DNS server
Resolves hostnames to IP addresses
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Example: www.yorktech.com is 172.16.2.11
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HOST file – contained names and aliases matched to IP
addresses – manually configured
DDNS – allows automatic additions of host
names to IP addresses
Platform independent
DNS Namespace
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Hierarchical structure with logical
divisions of domains
EDU
Winthrop.edu
COM
IBM.COM
GOV
DOC.gov
JP
Google.co.jp
NAT
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Network Address Translation
Allows many computers to connect to the
Internet through one connection
Static: server configured with an IP address
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External IP address(es) may be within the official
network IP address
Internal IP addresses used by nodes may be
private addresses
Dynamic: server assigns IP addresses from a
range to be used by hosts as they request
web access
ICS
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Windows version of NAT
Lacks security
SNMP
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Simple Network Management Protocol
Facilitates network management – it isn’t a
network management system (NMS) itself
NMS is a special software
Requires two modes
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Manager software
Agent software
Ability to monitor and manage hardware over
a WAN
IP Version 6
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Uses 128-bit addresses
Greater number of IP addresses.
Eight octets in Hexadecimal format
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Example:
52DF:7E22:63F2:21AA:CBD4:D77e:CC21:554F
Other features
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Smaller headers (lower overhead)
Packet labeling (prioritization)
Improved authenticity/security