Network+ : TCP/IP and Network Operations

  1. Network+ Certification
  2. Network+ Certification – Introductions and Resources
  3. Network+ : From Physical Topologies to Media and Network Devices
  4. Network+ : Networking Variants, Physical Installation
  5. Network+ : TCP/IP and Network Operations
  6. Network+ : Network Naming and Sharing Resources
  7. Network+ : IPv6
  8. Network+ : Remote, Secure and Cross-Platform Networking
  9. Network+ : Servers and Support
  10. Network+ : WiFi
  11. Routing and Firewalls
  12. Network+: Routing Protocols
  13. Network+: Network Monitoring

LAN Networking

The oldest network model:

Application

Communication

Physical

Network Operating Systems

Models:

        • Client/Server
        • Peer-to-Peer
        • Resource-Based (Workgroup)
        • Server-Based (Domain)
        • Organization-Based (Directory)

LAN Manager (LM) – 3Com and MS

 

NetBEUI/NetBIOS – IBM and MS

LAN only, using MAC addresses for addressing and NetBios for naming.

NetBIOS name: 15 chars. max

NetBIOS NW Model:

Application

NetBIOS (naming)

NetBEUI (addressing)

Physical

Novell/Netware

IPX/SPX

LAN only

WINS

MAC Resolution

MAC uses FRAMES (with MAC headers)

Broadcast address: FFFFFFFFFFFF  (12 Fs)

How do you tell if it’s local or remote?

arp -a
arp -d *

WAN Networking

DoD DARPA -> ARPA -> DARPA

DARPANET

80%

TCP/IP Model (DoD Model)

App

–> TCP –> intact delivery; UDP –> fast delivery

–> IP –> IP addresses

Physical

The ISO Model

ISO created the Open Systems Interconnect Model – the OSI Model

OSI and DOD Models
OSI and DOD Models

IP Networking

TCP/IP and UDP/IP

Gateways

Subnet Masking

DHCP

DNS

WINS

Class
First Octet
Number of addresses
A
1 – 126
16.7 Million
(loopback)
127
B
128 – 191
65,534
C
192 – 223
254

Classless Subnetting (CIDR)

Instead of expressing a 24-bit net mask as 255.255.255.0, express the number of bits directly: /24.

This makes a network number look like this:

192.168.1.0/24

Subnetting

First, you’ll need at least a basic understanding of how net masks work, and how you can lengthen the net mask to sub-network (subnet) an existing IP network.

Second, you’re likely to encounter questions that require a deeper understanding of how large a subnet will be, how many hosts it can support, and so on.

This is a great time to get familiar with StackExchange, if you haven’t already used it. Check out “How do you calculate the prefix, network, subnet, and host numbers?”
https://networkengineering.stackexchange.com/questions/7106/how-do-you-calculate-the-prefix-network-subnet-and-host-numbers

Non-Routable (LAN) Special Addresses (IEEE RFC 1918)

Class
A
10.0.0.0
10.255.255.255
B
172.16.0.0
172.31.255.255
C
192.168.0.0
192.168.255.255