Download WAN Data Networks

NET 3710
WAN Data Networks
Network Protocols
Protocols functions:









Communication control – how to communicate (peer to peer,
master/slave)
Error detection/correction – how to check for and correct
errors
Link management – control traffic flow
Session variables – login, authentication of users, half or full
duplex
Synchronization – transfer rates, timing
Addressing – unique ID for nodes; connection oriented
(circuit), or connectionless (packet)
Routing – metrics on how best to route traffic
Data segmenting/reassembly – frames, cells, packets,
header and trailer
Data formatting – Encryption and compression
Data Network Types
LAN – Local Area Network

Within a building
WAN – Wide Area Network

Network connecting LANs in many different
locations
Focus on WANs
WAN Types
Types of WANs
 Public – Internet
 Private – Private line, VPN, MPLS
XO IP Network
XO Network Maps
IP
Internet Protocol (IP) mainly an addressing
scheme
•
•
•
•
An IP address has two parts: the identifier of a particular
network on the Internet and an identifier of the particular
device (which can be a server or a workstation etc.) within
that network. On the Internet itself - that is, between the
routers that move packets from one point to another along
the route - only the network part of the address is looked at.
IPv4 uses a 32 bit address
IPv6 uses a 128 bit address and provides for better QoS
IP address hard to remember so Domain Name Service
(DNS) is used to translate names to IP addresses.
Private WAN Types
*Private Line (point to point) – Layer 1
 Dedicated circuits between locations TDM
or IP. TDM = T1/T3/OCx
 Pros – secure, reliable, dedicated
bandwidth not shared, supports any
protocol
 Cons – costly, many circuits to manage at
hub or main location
Private WAN Types
*Ethernet (WAN)
 Old layer 2 technology used on LANs
 Newer to WAN environment
 Implemented over SONET for protection or over
DWDM backbones
 10/100/1000MB speeds
 Interconnect LANs at Layer 2
 Point to point or switched (FE aggregation to GigE)
 Pros – matching LAN speeds, simple, cheap (per
MB), flat network
 Cons – flat network
Private WAN Types
Multiprotocol Label Switching (MPLS)
Layer 2 switching level
 Semi private/shared network
 Pros – utilizing existing backbone, scaleable, layer
2 – fast, one circuit to manage at HQ, cheaper than
private line
 Cons – shared type network, not dedicated

Private WAN Types
*Virtual Private Network (VPN)
Layer 3 (IP) utilizing existing Internet
 Traffic is encrypted for security
 Hub and spoke or Meshed network
 Pros – utilizing existing network (internet),
scaleable, layer 3, better use of bandwidth
 Cons – public network backbone, encryption
overhead

Network Convergence
Voice and data networks becoming one
 More efficient and economical
 Very attractive for branch office design
 Using dedicated or private circuits VOIP
works well.
 Utilizing the Internet for VOIP is still
unreliable.
