The latency tag has no wiki summary.
0
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1answer
28 views
What factors affect propagation time for wired / wifi multicast messages? [on hold]
I have a newbie question on multicast delivery times.
In this article on clock synchronisation they claim that the propagation time on a local network is close to zero.
What is the propagation time ...
1
vote
1answer
133 views
What causes packet loss when using full bandwidth from ISP?
We have a small, local ISP that is having some networking issues and I'm trying to understand the cause to better communicate with their network guys. I work with a number of companies with different ...
0
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3answers
82 views
How does latency affect a HTTP session? [closed]
I'm running a test where we introduce increased latency (round trip time, specifically) into a network connection between a client workstation and a web server. I'm seeing that added latency is ...
0
votes
1answer
350 views
difference between latency and delay measurments [closed]
In terms of links between two nodes on a network, what is the difference between latency and delay? They both seem to measure the amount of time from when a source transmits until the receiver ...
2
votes
2answers
99 views
Troubleshooting a wireless network
The following shows pings to the gateway of some university halls of residence:
How would you try to explain/troubleshoot such variance?
Is this normal for wireless networks?
I do not know of ...
1
vote
1answer
52 views
Can I somehow increase the latency / response time of a server for testing?
I am looking to make some speed performance tests. Normally our server responds within ~25 ms or so, but, I would somehow like to make it answer with delay. So basicly I would like to make some ...
2
votes
1answer
119 views
Cisco C891F-K9 ISR latency?
What is the multicast routing latency of Cisco C891F-K9 ISR? Please cite references for your answer. I think it's store-forward type and isn't one of the fastest models (given its price!).
I've ...
1
vote
1answer
1k views
Initial estimated round trip time in the RTT formula
I was reading about Round Trip Time (RTT) and then I came across this formula
EstimatedRTT = 0.9 * PreviousEstimatedRTT + 0.1 * Sample RTT
What is the value of PreviousEstimatedRTT when it is ...
1
vote
2answers
183 views
What is the difference between data rate and latency?
Both attempt to measure the speed of a network. If data rate is the thing that is commonly measure in Mbps and latency is the thing that is measured in milliseconds, what are their similarities and ...
1
vote
1answer
77 views
Troubleshooting Slowness in Stocks Trading Applications [duplicate]
Hi Fellow Network Enthusiasts!
I'm having a hard time troubleshooting a Real Time Stocks Trading Application. Here are the Steps I've done so far:
Apparently, this is the only Real-Time Application ...
0
votes
1answer
70 views
bandwidth vs latency - question on stuart cheshire paper
I am trying to get my grips around bandwidth and latency. I have read Stuart Cheshire's essay, however, there are a couple of paragraphs that I cannot understand.
Paraphrasing: Assume we are to ...
4
votes
3answers
284 views
Measuring per-link latency/jitter/packet-loss
I need to measure the latency, jitter and packet-loss per link in a network, as opposed to end-to-end, e.g. like this:
s1-eth0 <--> s2-eth0 (~ 20µs avg. latency, standard derivation 10µs, 57 % ...
6
votes
4answers
663 views
Can you reduce RTT by increasing the bandwidth on a link?
Does increasing the bandwidth on a link from lets say 1mb to 30mb reduce the RTT?
I have found one answer saying no. Can someone please explain?
Also, what is the best mechanisms to reduce RTT.
...
1
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0answers
84 views
Fast Network Slow to Start
Just moved into a new commercial space with great internet speeds, but frequently when using SFTP / FTP to transfer files it lags horribly.
Here is the setup:
Comes in via Comcast Cable to a Juniper ...
7
votes
2answers
3k views
Is daisy chaining switches increasing latency?
This is a general question not related to specific hardware. If we have the following configuration of daisy chained switches:
internet ---- core network ----- switch 1 ----- switch 2 ----- switch 3 ...
1
vote
0answers
275 views
Unknown IP as first hop when tracert [closed]
My friend who has the same provider(cable provider) and lives 2 streets from mine has 10-15ms less when we game online. We have the same modem and are both connected to a router.
We seem to not use ...
2
votes
2answers
881 views
How to reduce latency on ASA 5510 WAN link?
I have a Cisco ASA 5510 connecting our office via 2Mbit/s Internet. When Internet link fills up, latency to a well-connected host on Internet goes from 5-8 ms to 500-800 ms. With ping, it may look ...
4
votes
1answer
898 views
measure one-way latency/jitter/packet-loss
I'm getting increased latency and StDev due to route congestion and packet loss, but the forward and reverse paths go over distinct networks (e.g. one being init7.net, the other one being he.net), so, ...
1
vote
2answers
371 views
Cisco - MtR alternatives
I trying to establish if there is a function within IOS somewhere that can provide the same results of MTR , i know it can be run from Juniper devices / *Nix & Windows devices.
Goal is to ...
2
votes
3answers
1k views
Network Latency issues with Cisco AP
This question involves network latency as opposed to bandwidth. I have a small remote office with a single Cisco 881W integrated services router (Ethernet WAN). The WAN modem is an AdTran NetVanta ...
5
votes
3answers
582 views
High latency during downloads
I am having the same issue on my business connection 5Mbps as in another posting on this site. As soon as any computer starts a download the latency on the first hop past our DFG provided by our ISP ...
12
votes
2answers
2k views
Does physical distance affect download speed?
I just had an argument with a colleague of mine and thought I'd just reach out to the experts on this. Here's the scenario. We were using a website that measures your connection's speed. We tested ...
9
votes
2answers
323 views
Ultra-Fast Querying Using UDP Packets
I am implementing a system where one device on a network queries at a very high frequency (hundreds or thousands of queries per second) through sending a small UDP packet with 8 or so bytes of data. ...
8
votes
3answers
10k views
How to find the source of increased latency?
I've got monitoring setup on several devices in our office. The ping response time to small access switches is commonly 1-4ms... As of 3AM this morning, this has sky-rocketed to 300ms on average.
...
6
votes
4answers
786 views
Measuring Internet connection bandwidth [closed]
I need to recommend a reliable way for our clients to measure their Internet connection's bandwidth. Currently, I've been recommending www.speedtest.net for a number of reasons:
Easy to use ...
2
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0answers
132 views
Measuring latency upon SCTP reconfiguration [closed]
SCTP is a transport layer protocol message oriented like UDP, but it also provides reliability and in-order delivery as TCP. Furthermore, it natively supports multihoming therefore SCTP-based ...
10
votes
4answers
637 views
Do faster segments of a network mean faster flow rate or lower latency?
This is another one of those hypothetical questions. I've been trying to figure out whether or not having a faster 'segment' of a network in between host A and host B will translate into a faster flow ...
7
votes
6answers
601 views
Accurate strategy for measuring point-to-point link performance?
I have a requirement to provide an accurate means to demonstrate line performance over a flat layer2 1Gb point-to-point Ethernet circuit, approx 100 miles apart that seemingly goes through a number of ...
2
votes
2answers
217 views
How fast can information travel through various mediums?
I'm working on compiling some information about network latency and designing tests to help our support folks troubleshoot problems. In order to do this, I need some basic information that I don't ...
7
votes
4answers
167 views
Recording latency between a controlled startpoint and uncontrolled endpoint
This might be a very basic troubleshooting question, but it's worth asking to make sure I'm testing things the correct way and interpreting results effectively.
I have a controlled start point (a ...
5
votes
3answers
1k views
What is a reasonable latency for a L2 1G leased line between 2 sites, about 420km apart?
We need a dual gigabit connection to one of our customers and for the time being one of the lines has been brought online. The connection is between our DC and the customer's HQ, it's a L2 connection. ...
10
votes
11answers
9k views
What would cause high latency anytime there is traffic on WAN?
I have a network that has been experiencing slow internet speeds. After a great deal of troubleshooting, I have determined that any streaming content/downloads will cause the latency of WAN traffic to ...
