IP Primer

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IP Primer
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Introduction to Internet Protocol (IP)
Internet abbreviation of Internetworking, which
means the interconnection of networks (implies
computer networks). Telecom abbreviation of
Telecommunications, which is short for Telephone
Communications, which refers to the original goal
of these networks to transmit voice.
The objective here is to understand the
relationship between inter-networked computers
and the telecommunications network.
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Telecom vs. Computer Networks in a Building
TDM based voice (telecom) network
office
office
office
LAN
In an office environment there are typically two
separate networks. The telephone network for
voice and the IP network for transferring data
between computers
IP based data network
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Inter-Networking Model
Building - location 1
Building - location 2
There is no ability to phone or transfer data
between the two buildings until some form of
transmission network is established
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Transport Network / WAN
Building - location 1
Telecom Transport Network
Building - location 2
The phone system in each building is connected to
the public carrier telephone network. The
computer networks in each building are not
connected to the outside.
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Convergence of Two Major Networks
Office - location 1
Telecom Transport Network
Office - location 2
The computer networks in each building are now
connected to the public carrier telephone network
either through the telecom access equipment or
the computer network access equipment.
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Transmission Equipment in IP Networks

• Micro-Bridge
• Connects LANs together transparently
• Does not act on IP addresses
• Passes all data
• Hub
• Bridges all devices together
• Broadcasts to/from all ports
• Does not act on IP addresses
• Switch
• Bridges all devices together
• Does not act on IP addresses
• Buffers data to prevent collisions
• Router
• Routes data packets
• Directs traffic depending on IP addresses
• Compiles database of IP addresses
• Performs network address translation

• Typical interfaces include
• 10/100 BaseT Ethernet
• V.35
• T1/E1
• OC3/STM1

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Transmission Equipment in Telecom Networks

• Cross-Connect
• Cross connects digital signals between composite
  digital signals
• Multiplexer
• Separates a composite digital signal into its
  component digital signals
• Combines several digital signals into a single
  composite digital signal
• Provides various analog and digital interfaces
  for different applications and legacy telecom
  equipment

• Typical interfaces include
• 2-wire FXO
• 2-wire FXS
• 2-wire EM
• 4-wire EM
• OMNI-Bus
• 10/100 BaseT Ethernet
• V.35
• RS232
• RS422
• E1
• T1

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Core Equipment

• At the core of a telecom network is a Switch
  which
• Establishes dedicated paths for the passage of
  messages between two or more terminals
• Routes calls from one Central Office to the next
  as required
• Provides instantaneous communications where the
  switching process introduces no perceptible delay
  between receipt and delivery of a message
• There is no core of a computer network. It is
  completely distributed.

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Consideration Distance Application
In the end the goal is to produce the desired
quality of voice, video and data communication
between any pair of desired locations, whether
the distance between locations is 1m or 10,000
km.
The distance between the locations determines the
type of transmission equipment. The application
interface determines the type of access
equipment.
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Point-to-Point Ethernet Bridge
Micro-Bridge provides simple point-to-point
10BaseT extensions across an T1/E1 TDM link
T1/E1
DCM6 4
DCM6 4 N
OMNIPlexer with DCM64N V.35 data card
DCM6 4
DCM6 4 N
OMNIBridge
OMNIBridge
Work Station

• Application
• Connect remote devices to a LAN

Work Station
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Ethernet Hub Layer 2 Bridging

• Hub enables simple bridged connectivity to
  support multiple devices
• 10BaseT connections to devices and backhaul
  channel
• Backhaul over TDM T1 or E1 link

Microwave
Backhaul
M13
Internet Access
Remote Base Stations
Base Stations
Backhaul T1/E1s
OMNIHub 10BaseT Hub and Terminal Server

• Applications
• Management system
• Concentration in low-throughput
• situations

OMNIFlex
E911 Location Sensor V.35 or T1, 1xDS0
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Integrated IP and TDM Network

• Router supports both IP and TDM traffic
• Router directs IP traffic between LAN and remote
  devices
• OMNIPlexer supports analog traffic
• Router supports NxT1/E1 and T3/E1
• Backhaul over NxT1/E1 or T3/E3

OMNIRoute
OMNIRoute
OMNIPlexer
T1/E1
T1/E1
T1/E1
10BaseT
OMNIPlexer
OMNIHub 10BaseT Hub and Terminal Server
10BaseT
Analog
RTUs

• Applications
• Remote LAN access
• RTU connectivity
• Hybrid TDM and IP traffic

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IP over TDM Network

• Router supports both IP and TDM traffic
• Router directs IP traffic between LAN and remote
  devices
• OMNIPlexer supports analog traffic
• Router supports NxT1/E1 and T3/E1
• Backhaul over NxT1/E1 or T3/E3

OMNIPlexer
T1/E1
OMNIRoute
V.35
Analog trunks
Management
10BaseT
10BaseT
RTUs

• Applications
• Hybrid IP and TDM traffic
• Remote LAN access
• RTU connectivity

Master Station
Server
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Integrated TDM and IP Network

• Router directs IP traffic between LAN/3G MTSO
  and remote devices
• OMNIFlex supports TDM traffic CSU/performance
  monitoring functions
• Router supports IP traffic over NxT1/E1 and T3/E1

NxT1/E1
OMNIFlex
NxT1/E1
OMNIRoute
OMNIRoute
TDM MTSO
TDM Base Station NxT1/E1
OMN Ihub 10BaseT Hub and Terminal Server
IP Switch
Management
3G MTSO

• Applications
• Hybrid TDM and IP networks
• Transport over T1/E1 facilities

3G IP Base Stations 10BaseT
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TDM vs ATM vs IP

• We have found it very interesting watching
  customers react to the Future.
• Several aspects really stand out
• It becomes a very political issue
• The major vendors are pushing new technologies
  very hard and assume the operators will abandon
  older technologies
• Not many people really know what is involved
• No one addresses the reality of hybrid networks
  (ie IP and TDM)

TDM MicroDACS
?
IP Router
ATM Switch
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TDM vs ATM vs IP
.in wireless networks A major Wireless operator
spent one year debating TDM vs ATM vs IP for
their edge-of-network optimization. They finally
decided on the TDM solution. Before they bought
any equipment they started considering ATM again
then wondered if IP was better. They spent
another year debating TDM vs ATM vs IP. At the
end of the second year they finally confirmed
that TDM was the right solution. Two months later
they bought Lucents ATM equipment!!!
Note the payback for the TDM equipment was 5
months. It took 26 months to make a decision.
They could have saved millions
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TDM vs ATM vs IP
.in wireless networks Another Wireless operator
tested TDM MicroDACS for two years. Once the
equipment was approved they spent over one year
debating TDM vs ATM. for their edge-of-network
optimization. They finally decided on the ATM
solution and spent millions over the next 18
months before realizing that the ATM product is
very expensive, very difficult, very problematic
and not necessary. Some regions refused to
implement the equipment. Some regions continued
to buy the TDM solution because they felt the ATM
made no sense.
Note the payback for the TDM equipment was 5
months. It took 36 months to make a decision.
They could have saved millions
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TDM vs ATM vs IP
Three years ago the head of engineering for a
national wireless carrier announced that they
could not use a TDM MicroDACS for their network
because their base stations were all going to be
IP. This year they are implementing the TDM
MicroDACS nationwide.
TDM MicroDACS
?
ATM Switch
IP Router
Note the payback for the TDM equipment was 5
months. It took over 36 months to make a decision.
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TDM vs ATM vs IP

• Other considerations include
• The reality of maintaining a WAN/LAN
• The difficulty of troubleshooting an IP network
• The needs of a carrier network vs. a private
  network
• IP still needs some type of backhaul!!!!!