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2 answers

VPLS Multihoming on Junos - FEC confusion‏

I'm going over the VPLS multihoming options on Juniper's web site. I'm not concerned with LAG and MC-LAG for the moment. As far as I'm aware: FEC128 is when you are using manual discovery of pseudowires (LDP) FEC129 is when you are using BGP…
mellowd
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What layer of the OSI model does NAT work?

Simple question and the answer is layer 3 of course, but can we say that PAT is working on layer 4 also because it deals with port numbers which is a layer 4 function? Or is it only a layer 3 protocol?
aia87
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JunOS: Password recovery has failed

I am trying to recover a root password on an MX80 but I'm receiving some errors and have no idea what they mean (it's not live so suggestive "disruptive" steps is acceptable); The steps I have taken are as follows; Reboot the router, at the prompt…
jwbensley
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13
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3 answers

What is the purpose of an Ethernet magnetic transformer, and how are they used?

I have been told that Ethernet magnetic transformers are used for base-t Ethernet when transmission is sent over a lengthy cable. What is the purpose of the transformer? (is it for signal filtering or boosting?) Additionally, I have a circuit that…
Benjamin
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13
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Point Of Presence vs. Central Office

What is the difference between these two (in distance and function)? I understand that a Central Office is a place where the ISP stores equipment that connects many clients. But the POP has a similar definition. It is a place where many clients…
BrunoMCBraga
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13
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3 answers

OSPF Stuck in Exstart Adjacency State

According to this article two routers will get stuck in the exstart adjacency state when their configured MTU sizes do not match. Does a VLAN tag affect this as well even if the routers involved are unconcerned with which VLAN the packet is coming…
JDGray
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13
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2 answers

Are there any global network other than the Internet?

I found this definition of Global Networks: Currently does any Global Network exists (apart from Internet)? Can someone Quote some examples? Or non-global but on a country-wide scale(ATM network maybe)? Doesn't every other WAN network comes under…
Jarwin
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13
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3 answers

I want to perform monitoring of my network infrastructure, can this safely be done with SNMPv2?

I need to perform monitoring of my network infrastructure but I'm wondering if using SNMPv2 is secure? What are the weaknesses of SNMPv2?
Lucas Kauffman
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13
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2 answers

Open a range of TCP ports in Cisco IOS NAT

ip nat inside source static 192.168.1.10 10.10.10.9 route-map RANGE ! route-map RANGE permit 100 match ip address 102 ! access-list 102 permit tcp host 192.168.1.10 range 3000 3389 any The configuration does not seem to work.. just creates a one…
Luna
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13
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2 answers

Simulating a poor network

I'd like to set up a poor wifi network in my office for developers to test on. What is the best way to simulate real world crappy wifi? High latency? Dropped packets? low bandwidth?
SAR622
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4 answers

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. Where does one start looking in a situation like…
A L
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13
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4 answers

How do you block bit torrent traffic with a Cisco ASA?

I have referenced an old external Cisco article on how to block Bit torrent traffic referenced on-line Here This procedure I have found only works 50% of the time. I find blocking bit torrent specific ports, and doing the regex do work, it just…
Blake
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13
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7 answers

How can I generate traffic on a Cisco ASA?

In a lot of locations, we have only one Cisco ASA 5505 each and one or more WiFi APs, besides the provider router. No servers or PCs, just WiFi service for occasional visitors. I want to remotely check if the provider gives us the contracted…
Stefan
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13
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4 answers

Why do switches need ARP tables when the translation are done on the machines side?

As it is clear from the title, why do switches need ARP tables when the translation are done on the machines side? Roughly saying, why there are two ARP tables on machines and on switches? Is not the one on the switch sufficient?
محمد جعفر نعمة
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How can I verify QoS DSCP marking on a Cisco Catalyst 4500E?

Good afternoon, I've got a shiny new 4500E running 15.0(1r)SG7 that is set to replace an ailing 3750E. It is running ipbase for now. On the 3750 I was able to check out the incoming DSCP/CoS values on interfaces using the sh mls qos int gigX/X/X…
Mike
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