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1500 questions
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1 answer

IPv6 replacement for ICMP timestamp

Does any standard IPv6 protocol has anything analogous to an ICMP timestamp message?
cnst
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6
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2 answers

How does the ARP table work in case of the Gateway Router?

Suppose I am a host, I understand how ARP works in case I address an IP within my subnet. For each IP address there is a corresponding MAC address, and the owner responds to my broadcast ARP query. However, for external IPs, my ARP table is actually…
Ninja Bug
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6
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2 answers

Network Ten LTE Hubs Into One Network

I'm working through a tricky situation getting a field office set up out in a very rural area. There are ten 12' x 60' trailers being set up (2-3 metres apart from one another), each with varying amounts of staff working during the day (40-50 people…
Markus
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6
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4 answers

Packet Collison Avoidance

If a wireless network has collision avoidance, how comes the network slows down if more clients connect to it?
LtMuffin
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6
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1 answer

Cisco ASA: which side is "inside" with same security-level?

I have an issue with an FWSM apparently killing RDP sessions after a random amount of time, and the log entry looks like: Teardown TCP connection 145379776990678860 for MS_LZ1:10.30.3.150/49924 to LZ1_MS:10.254.0.217/3389 duration 0:01:58 bytes…
AnotherHowie
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6
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1 answer

Max AS path to accept from peer?

I heard that once AS receives a BGP update that is longer than 50, it will be dropped. Is this true or just happens with some ISPs specifying that policy? I cannot find any evidence or official documents regarding this. It's great if anyone can…
Muoi Tran
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6
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1 answer

How to use tcp-udp objects in a single ACL?

I have a service object group of type 'tcp-udp'. When creating an ACL based around this, I don't have the option of type 'tcp-udp'. I'm trying to figure out what the point of tcp-udp groups are, if at the end of the day you still have to make two…
A L
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6
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2 answers

VRFs to address asymmetric routing with stateful inspection

For branch offices with dual routers and WAN connections asymmetric routing causes issues with stateful packet inspection. Packets leaving through one router and returning through the other are dropped as the return router's stateful firewall knows…
Stephen Craven
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6
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3 answers

If there's no response to the ARP request, will the host send to its default gateway?

Host A and B are on the same subnet. A sends ARP request(s) asking for B's MAC. For whatever reason, B doesn't respond. Will A either: Give up -- it can't reach B Send the packet to the default gateway, router R, and let it try to route it to…
SRobertJames
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6
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2 answers

Cisco Router (ISR4221) Throughput - Why so slow?

I'm looking for a new router for a new branch of hour company. I got experience with cisco L2 & L3 Switches but not that much with Routers. I was looking at the ISR4000 series, specifically the ISR4221. In the datasheet it's stated that the…
Geo
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6
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5 answers

Does a Layer 3 switch become a Layer 4 device when telnetting?

In order to Telnet to a switch (Layer 2) we create an SVI, thus a layer 3 point of contact is made. The switch inspects each packet sent from the remote client and responds to it so that it gets configured. In that case is it true that the switch…
Peter
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6
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6 answers

Why doesn’t ICMP use port numbers?

Firewall is showed in port no 7 and Google search is also showed in port no 7 so I am confused about how exactly ICMP use the port number. Regards, Bhushan
Bhushan Wankhede
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6
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2 answers

Cisco 6509 Supervisor Card Slot Boot Failure

We recently had a sporadic reboot of a distribution switch for an unknown reason. No recent hardware/software changes have been made. Our log files don't indicate anything leading up to the incident. The system is a 6509-E running software version…
Ryan Foley
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6
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2 answers

SPAN impact on ASA performance

I am planning to mirror some traffic on an ASA 5510 running version 9.1. this traffic is mostly internet data which cannot exceed 30 Mbps. what impact could this SPAN operation cost me on performance ? and is there any security concerns when trying…
Hamdi Kadri
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6
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1 answer

Does TCP Cwnd keep increasing if transfer is limited by Rwnd?

I'm trying to understand what happens to the TCP Congestion Window (Cwnd) if the transfer rate is limited by the Receive Window (Rwnd). I know that the transfer rate is the minimum of Rwnd and Cwnd. I also know that Cwnd increases for each ACK…
EM0
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