CS 6250 Computer Networks Exam 2 |
Practice Questions and Correct
Answers | Graded A+
What is CIDR? Classless internet Domain Routing
- Correct Answer - Assigns IP addresses using arbitrary-length prefixes.
Decreases the router table size but then brings us a problem of longest-
matching-prefix lookup
Why do we need packet classification?
- Correct Answer - Finer packet handling (TCP flags, source addresses,
etc)
3 variants of packet classification
- Correct Answer - 1. firewalls: routers implement firewalls at the entry
and exit points of the network to filter traffic
2. resource reservation protocols: reserve bandwidth between source
and a destination
3. routing based of traffic type: routing based of specific traffic helps
avoid delays for time-sensitive applications
3 Simple solutions to packet classification and what are they?
,- Correct Answer - 1. Linear search: Firewall implementations perform a
linear search of the rules database and keep track of the best-match rule
2. Caching: Another approach is cache results. two problems, miss rate.
3. Passing Labels: MPLS, a label-switched path is setup bt 2 sites.
Before traffic leaves site A, a router maps the web traffic into an MPLS
header. Thus redoing packet classification is not needed.
What spurred the development of SDN?
- Correct Answer - 1. Diversity of equipment: Too many different tools
make network management complex
2. Proprietary Technologies
What are the three phases in history of SDN?
- Correct Answer - 1. Active Networks
2. Control and data plane separation
3. OpenFlow API and network operating systems
Active Networks summary
- Correct Answer - resulted in
1. programmable functions in the network to lower the barrier to
innovation
2. Network virtualization, and the ability to demultiplex to software
programs based on packet headers
, 3. the vision of a unified architecture for middlebox orchestration
Control and data plane separation summary
- Correct Answer - Open interface between control and data planes
Logically centralized control of the network
openflow API summary
- Correct Answer - generalizing network devices and functions
the vision of a networked operating system
distributed state management techniques
What is the function of the control and data planes?
- Correct Answer - Selecting between network paths based on current
traffic load
Minimizing disruption during outages
Redirecting/dropping suspected traffic
Allowing customer networks more control over traffic flow
Offering value-added services for VPN customers
Why separate control plane from the data plane?
Practice Questions and Correct
Answers | Graded A+
What is CIDR? Classless internet Domain Routing
- Correct Answer - Assigns IP addresses using arbitrary-length prefixes.
Decreases the router table size but then brings us a problem of longest-
matching-prefix lookup
Why do we need packet classification?
- Correct Answer - Finer packet handling (TCP flags, source addresses,
etc)
3 variants of packet classification
- Correct Answer - 1. firewalls: routers implement firewalls at the entry
and exit points of the network to filter traffic
2. resource reservation protocols: reserve bandwidth between source
and a destination
3. routing based of traffic type: routing based of specific traffic helps
avoid delays for time-sensitive applications
3 Simple solutions to packet classification and what are they?
,- Correct Answer - 1. Linear search: Firewall implementations perform a
linear search of the rules database and keep track of the best-match rule
2. Caching: Another approach is cache results. two problems, miss rate.
3. Passing Labels: MPLS, a label-switched path is setup bt 2 sites.
Before traffic leaves site A, a router maps the web traffic into an MPLS
header. Thus redoing packet classification is not needed.
What spurred the development of SDN?
- Correct Answer - 1. Diversity of equipment: Too many different tools
make network management complex
2. Proprietary Technologies
What are the three phases in history of SDN?
- Correct Answer - 1. Active Networks
2. Control and data plane separation
3. OpenFlow API and network operating systems
Active Networks summary
- Correct Answer - resulted in
1. programmable functions in the network to lower the barrier to
innovation
2. Network virtualization, and the ability to demultiplex to software
programs based on packet headers
, 3. the vision of a unified architecture for middlebox orchestration
Control and data plane separation summary
- Correct Answer - Open interface between control and data planes
Logically centralized control of the network
openflow API summary
- Correct Answer - generalizing network devices and functions
the vision of a networked operating system
distributed state management techniques
What is the function of the control and data planes?
- Correct Answer - Selecting between network paths based on current
traffic load
Minimizing disruption during outages
Redirecting/dropping suspected traffic
Allowing customer networks more control over traffic flow
Offering value-added services for VPN customers
Why separate control plane from the data plane?
