CS 6250 Exam 2
2 states of playout buffer. Pattern? - ANS-1. Filling country - buffer is empty, have to be
crammed ASAP
2. Consistent kingdom - buffer is complete, wait til it's far lower than a threshold. Ship
request for more content material
on-off styles
3 categories of multimedia packages - ANS-1. Saved audio and video (youtube)
2. Conversational voice and video over IP (skype_
3. Streaming stay audio/video (grad rite)
4 functions of signaling protocols? - ANS-1. Consumer region - establish vicinity
2. Consultation established order - deal with endpoints accepting or rejecting call
3. Session negotiation - endpoints sync with every other on set of homes for the consultation
four. Name participation control - cope with endpoints becoming a member of or leaving
four goals of precise Quality of enjoy/ bitrate model - ANS-1. Low rebuffering
2. Excessive video best
3. Low fine variations
four. Low startup latency
Are blocklists at 2 unique GFW places extraordinary? Why? - ANS-No, due to GFW
supervisor
(10)
Are disbursed controllers fault tolerant? - ANS-Yes
(eight)
Are procedures clustered or separated with load balancing? Why? - ANS-clustered -
together ship DNS responses
(10)
Are SDNs built on open, trendy interfaces? Why? - ANS-Yes. Configuration and
conversation compatibility may be among distinct apps and devices
(eight)
Are southbound APIs a barrier for reputation of SDN era? What will fix this? - ANS-Yes. API
proposals that standardize those southbound APIs, like Openflow, deal with this
(8)
blockading with resets vs. Immediately reset of connections - ANS-- content based vs.
Identity (supply) based totally
(10)
can upstream provider/IXP assist with blackholing? How? - ANS-Upstream AS drops traffic
toward victim
issuer advertises greater unique prefix, and modifies next hop address
,provides blackholing community characteristic
traffic goes to null interface (and is dropped)
(9)
Compare bitrate for video, picture, audio - ANS-1. Video
2. Image
three. Audio (marginally decrease than photo)
Did active network do anything for overall performance? Security? - ANS-No (7)
Did openflow prevent small players from being competitve? Why - ANS-No, have become
extra aggressive b/c they may just focus on writing manage packages instead of proprietary
switches
(7)
Difference among DNS injection and TCP RSTS - ANS-TCP RSTS allow blockading of
individual connections, DNS injections block whole area call
(10)
Difference among rogue and professional networks? - ANS-- durability of malicious behavior
- official networks can cast off them plenty extra speedy
(9)
downside of http get for video? - ANS-1. Down load is a waste if users leave
2. Buffering downloaded however unplayed facts
Do distributed controllers have weak consistency of semantics? - ANS-Yes
(eight)
Do SDNS have a physically centralized control plane? - ANS-No, bodily DISTRIBUTED
(8)
Do SDNs have logically distributed controller? - ANS-No, logically CENTRALIZED
(eight)
Does FIRE take a look at networks w/ malicious IP addresses which have been up for a brief
period of time? - ANS-No due to the fact legitimate networks can eliminate content material
faster
(9)
Does majority think GFW nodes present only at side IPs? - ANS-Yes - most effective at facet
(10)
Explain 3 types of AS-path statement hijacking - ANS-- Type-zero - announce prefix not
owned through itself
- Type-N - announce illegitimate route to prefix it would not own
- Type-U does no longer alter AS-PATH however changes prefix
(nine)
Explain three sorts of category by means of affected prefix: - ANS-- actual prefix hijacking:
announce course for same prefix
- sub-prefix hijacking - announce traffic for extra particular, sub prefix
- squatting - promote it deal with that belongs to a distinctive AS
,(9)
Flowspec vs. ACL filters? - ANS-Flowspec uses manage plane
less complicated to feature rules to routers
(9)
How are selections for forwarding and coverage made inside ONOS? - ANS-data is fed on
from view
coverage choices are made
replace the decisions made lower back the view
(8)
How can paintings be disbursed within ONOS? - ANS-Add extra times in ONOS cluster
(eight)
How did better hyperlink speeds in spine networks encourage control and statistics plane
separation? - ANS-packet forwarding applied in hardware, become independent from
manage aircraft (7)
How do CDNs and RRDNS advantage scammers? - ANS-- Harder to close down on-line
scams because if simply one IP is practical, it nonetheless works
(nine)
How do speedy flux provider networks work? - ANS-DNS information are quick lived (low
TTL)
They return a set of data which might be best a small percentage of the to be had IP
addresses for that domain
they belong to compromised machines to act as proxies
they shape a resilient one-hop overlay community
(nine)
How do hybrid distributed controllers work? - ANS-- clusters of controllers in a data middle,
dispensed nodes in one of a kind websites
(8)
How do researchers discover GFW censorship techinuqes - ANS-- active probing
- vantage factors
(10)
How do SDNs address obstacles of BGP? - ANS-- suit numerous header fields, now not just
destination prefix
(eight)
How do switches the usage of P4 forward packets? - ANS-- use a programmable parser
- use set of fit + motion tables to ahead packets
- in shape + action tables can be accessed in PARALLEL
(eight)
How does an openflow switch work? - ANS-Switch has TABLE OF PACKET HANDLING
RULES
each rule has a sample, list of moves, set of counters, and precedence
whilst packet is received, the switch:
- determines maximum precedence matching rule
, - plays movement
- increments counter
(7)
How does analog audio encoding work? What is the time period for the manner? -
ANS-Approximate analog wave with the samples in line with second, known as quantization
How does Augur come across filtering among hosts? - ANS-IP ID identifier/international
counter - incremented for every packet generated by way of a host
while surprising TCP packet is despatched, it sends a TCP reset packet
How does patron recognise approximately available bitrates - ANS-Manifest file with
metadata info, downloaded FIRST
How does DNS content material-based transport paintings? - ANS-DNS returns IP that
represents "nearest area" server to the customer
nearest server is calculated based on community topo and traits of link
TTL is LOWER than RRDNS
(9)
How does FIRE decide a rogue AS? - ANS-- each data supply provides list of malicious IPs
daily
- maximum ratio of of malicious IP deal with compared to total IPs in AS
(nine)
How does generalization of packet processing work with p4? - ANS-- layout of not unusual
language to write down packet processing applications INDEPENDENT of underlying
devices
- compiler maps programs to exclusive devices
(eight)
How does chance of breach use random woodland? - ANS-- uses a RF classifier, and
compares it to the baseline
- produces danger possibility
- thresholding the price
(9)
How does openflow deal with the increasing wide variety of header fields? - ANS-flexible
approach to healthy headers
P4 allows configuring switch programmatically
controller can define how switches perform
(eight)
How does p4 improve openflow with forwarding packets and accessing tables? - ANS--
openflow helps simplest fixed parsers primarily based on PREDETERMINED header fields
- openflow supports most effective a sequence blend of in shape+motion tables
(eight)
How does packet filtering paintings? Is it smooth to detect? - ANS-- Security mechanism -
block packets that fit positive standards to disrupt everyday forwarding
2 states of playout buffer. Pattern? - ANS-1. Filling country - buffer is empty, have to be
crammed ASAP
2. Consistent kingdom - buffer is complete, wait til it's far lower than a threshold. Ship
request for more content material
on-off styles
3 categories of multimedia packages - ANS-1. Saved audio and video (youtube)
2. Conversational voice and video over IP (skype_
3. Streaming stay audio/video (grad rite)
4 functions of signaling protocols? - ANS-1. Consumer region - establish vicinity
2. Consultation established order - deal with endpoints accepting or rejecting call
3. Session negotiation - endpoints sync with every other on set of homes for the consultation
four. Name participation control - cope with endpoints becoming a member of or leaving
four goals of precise Quality of enjoy/ bitrate model - ANS-1. Low rebuffering
2. Excessive video best
3. Low fine variations
four. Low startup latency
Are blocklists at 2 unique GFW places extraordinary? Why? - ANS-No, due to GFW
supervisor
(10)
Are disbursed controllers fault tolerant? - ANS-Yes
(eight)
Are procedures clustered or separated with load balancing? Why? - ANS-clustered -
together ship DNS responses
(10)
Are SDNs built on open, trendy interfaces? Why? - ANS-Yes. Configuration and
conversation compatibility may be among distinct apps and devices
(eight)
Are southbound APIs a barrier for reputation of SDN era? What will fix this? - ANS-Yes. API
proposals that standardize those southbound APIs, like Openflow, deal with this
(8)
blockading with resets vs. Immediately reset of connections - ANS-- content based vs.
Identity (supply) based totally
(10)
can upstream provider/IXP assist with blackholing? How? - ANS-Upstream AS drops traffic
toward victim
issuer advertises greater unique prefix, and modifies next hop address
,provides blackholing community characteristic
traffic goes to null interface (and is dropped)
(9)
Compare bitrate for video, picture, audio - ANS-1. Video
2. Image
three. Audio (marginally decrease than photo)
Did active network do anything for overall performance? Security? - ANS-No (7)
Did openflow prevent small players from being competitve? Why - ANS-No, have become
extra aggressive b/c they may just focus on writing manage packages instead of proprietary
switches
(7)
Difference among DNS injection and TCP RSTS - ANS-TCP RSTS allow blockading of
individual connections, DNS injections block whole area call
(10)
Difference among rogue and professional networks? - ANS-- durability of malicious behavior
- official networks can cast off them plenty extra speedy
(9)
downside of http get for video? - ANS-1. Down load is a waste if users leave
2. Buffering downloaded however unplayed facts
Do distributed controllers have weak consistency of semantics? - ANS-Yes
(eight)
Do SDNS have a physically centralized control plane? - ANS-No, bodily DISTRIBUTED
(8)
Do SDNs have logically distributed controller? - ANS-No, logically CENTRALIZED
(eight)
Does FIRE take a look at networks w/ malicious IP addresses which have been up for a brief
period of time? - ANS-No due to the fact legitimate networks can eliminate content material
faster
(9)
Does majority think GFW nodes present only at side IPs? - ANS-Yes - most effective at facet
(10)
Explain 3 types of AS-path statement hijacking - ANS-- Type-zero - announce prefix not
owned through itself
- Type-N - announce illegitimate route to prefix it would not own
- Type-U does no longer alter AS-PATH however changes prefix
(nine)
Explain three sorts of category by means of affected prefix: - ANS-- actual prefix hijacking:
announce course for same prefix
- sub-prefix hijacking - announce traffic for extra particular, sub prefix
- squatting - promote it deal with that belongs to a distinctive AS
,(9)
Flowspec vs. ACL filters? - ANS-Flowspec uses manage plane
less complicated to feature rules to routers
(9)
How are selections for forwarding and coverage made inside ONOS? - ANS-data is fed on
from view
coverage choices are made
replace the decisions made lower back the view
(8)
How can paintings be disbursed within ONOS? - ANS-Add extra times in ONOS cluster
(eight)
How did better hyperlink speeds in spine networks encourage control and statistics plane
separation? - ANS-packet forwarding applied in hardware, become independent from
manage aircraft (7)
How do CDNs and RRDNS advantage scammers? - ANS-- Harder to close down on-line
scams because if simply one IP is practical, it nonetheless works
(nine)
How do speedy flux provider networks work? - ANS-DNS information are quick lived (low
TTL)
They return a set of data which might be best a small percentage of the to be had IP
addresses for that domain
they belong to compromised machines to act as proxies
they shape a resilient one-hop overlay community
(nine)
How do hybrid distributed controllers work? - ANS-- clusters of controllers in a data middle,
dispensed nodes in one of a kind websites
(8)
How do researchers discover GFW censorship techinuqes - ANS-- active probing
- vantage factors
(10)
How do SDNs address obstacles of BGP? - ANS-- suit numerous header fields, now not just
destination prefix
(eight)
How do switches the usage of P4 forward packets? - ANS-- use a programmable parser
- use set of fit + motion tables to ahead packets
- in shape + action tables can be accessed in PARALLEL
(eight)
How does an openflow switch work? - ANS-Switch has TABLE OF PACKET HANDLING
RULES
each rule has a sample, list of moves, set of counters, and precedence
whilst packet is received, the switch:
- determines maximum precedence matching rule
, - plays movement
- increments counter
(7)
How does analog audio encoding work? What is the time period for the manner? -
ANS-Approximate analog wave with the samples in line with second, known as quantization
How does Augur come across filtering among hosts? - ANS-IP ID identifier/international
counter - incremented for every packet generated by way of a host
while surprising TCP packet is despatched, it sends a TCP reset packet
How does patron recognise approximately available bitrates - ANS-Manifest file with
metadata info, downloaded FIRST
How does DNS content material-based transport paintings? - ANS-DNS returns IP that
represents "nearest area" server to the customer
nearest server is calculated based on community topo and traits of link
TTL is LOWER than RRDNS
(9)
How does FIRE decide a rogue AS? - ANS-- each data supply provides list of malicious IPs
daily
- maximum ratio of of malicious IP deal with compared to total IPs in AS
(nine)
How does generalization of packet processing work with p4? - ANS-- layout of not unusual
language to write down packet processing applications INDEPENDENT of underlying
devices
- compiler maps programs to exclusive devices
(eight)
How does chance of breach use random woodland? - ANS-- uses a RF classifier, and
compares it to the baseline
- produces danger possibility
- thresholding the price
(9)
How does openflow deal with the increasing wide variety of header fields? - ANS-flexible
approach to healthy headers
P4 allows configuring switch programmatically
controller can define how switches perform
(eight)
How does p4 improve openflow with forwarding packets and accessing tables? - ANS--
openflow helps simplest fixed parsers primarily based on PREDETERMINED header fields
- openflow supports most effective a sequence blend of in shape+motion tables
(eight)
How does packet filtering paintings? Is it smooth to detect? - ANS-- Security mechanism -
block packets that fit positive standards to disrupt everyday forwarding
