2.5 Compare and contrast WAN technologies. Flashcards
What is DSL
Digital Subscriber Line. Service through the phone line :-)
How does DSL work
is a type of high-speed internet connection that uses existing telephone lines to transmit data without interfering with voice service.
Two types of DSL connections.
- Symmetrical: Symmetrical connection provides equal bandwidth for upload and download.
- Asymmetrical: It provides more bandwidth for download and less for upload since downloading rate is higher when compared to uploading for most users.
Disadvantages of DSL
Performance degrades as the distance between the Central Office and the user increases.
What is coaxial cable?
Cable Internet uses coaxial cable TV Cable connection to provide Internet services.
Disadvantages of Cable
but one of the disadvantages is shared bandwidth among the neighbors, which can degrade the performance if multiple users are connected at the same time.
What is a Leased line
is a leased dedicated circuit between two endpoints (locations)
Advantage of leased line
It provides high speed, maximum bandwidth, higher security and good QoS (Quality of Service) since the user gets Internet services over a connection that is just dedicated to them and not shared with anyone.
What is a Site to Site Data Connection:
leased line provider will provide the leased lines to different locations.
what is a Site to Network Connection
In a site to network leased connection, the leased line provider will provide the leased line to the user and provide Internet services at the same time.
What is Metro-Optical connection
The most common type of connection. It is to provide Fiber optical connection to the end-users as much as possible.
What are copper cables
made of copper. It uses pulses of electric signals to transmit data.
Unshielded Twisted Pair Cable (UTP)
8 copper wires twisted in pairs forming 4 pairs
Speed and length of Unshielded twisted pair.
The speed can vary between 10 to 1000 Mbps, and the maximum segment length of this cable can be 100m.
Shielded Twisted Pair Cable (STP):
8 copper wires twisted in pairs forming 4 pairs. Each Pair is shielded with a metallic foil. Good for noise reduction in areas with lots of interferance. Should be grounded.
Speed and length of Shielded Twisted Pair Cable (STP):
The speed can vary between 1000 Mbps to 40 Gbps, and maximum segment length for this cable can be 100m.
What is Mbps and how large is one
megabits per second. A million bits. or a about one small photo per second.
what is GBPS
What is a bit?
zero or one.
What is MBps
MegaBytes per second.
How many bits is a byte?
8.
PRI
Satellite
Wireless
MPLS
Multiprotocol Label Switching. Replacement for Frame Relay and ATM Switching
What does MPLS do
sends packets along predetermined network paths
What is Routing?
Routers refer to internal routing tables to make decisions about how to route packets along network paths.
ATM Service
Frame relay service
PPPoE
Point to point protocol over Ethernet. Encapsulate PPP frames into ethernet frames. Also more secutiry forcing you t o sign into DSL to use it.
PPP protocol
DMVPN
Dynamic multi point VPN. enables direct VPN connections between Mutiple locations directly.
SIP and H.323
Session Initiation protocol. Handles the initiation, setup and delivery of VoIP sessions. Also enables multicasting.
SIP and H.323 both run on top of
Real-time Transport Protocol (RTP)
PG 253
Most VoIP solutions are either
SIP/RTP of H.323/RTP
Demarcation point
Where the outside world and home/office connection meets.
If something brakes on your side it’s your problem on ISP side it’s theres.
CSU/DSU
Smart jack
MLPS Label
A unique identifier used by MPLS capable routers to determin how to move data
MPLS Experimental Bits (exp)
A A relative calue useed to determine the importance of the labed packer to be able to prioritize some pacjets over others
Bottom of label stack (S)
single packet may have multiple MPLS labels. Single bit value is set to 1 for the initial label
MPLS topology
MPLS routers use their existing dynamic routing protocols to send each other messages about their overhead.
TTL
A vaule that dermines the number of hops the labes can make before it’s eliminated.
QoS
Sorting IP packets to provide priority based on header info.
What do MPLS routers do
avoid running packets through a routing table and instead use header info to route packets quickly.
What marks where a service provirer responsibiles ends and the company responibity begins?
Demarcation point
DOCSIS us used by whch type of company
Cables
What is DOCSIS
Data over cable service interface spectification
MPLS lables are located between which two layers of
Ethernet frame at layer 2 and IP packet at layer 3
CSU/DSU
Channel service unit/digital service unit
