Does your Wave2 AP need NBase-T?

Cisco recently launched the 2800 and 3800 series 802.11ac wave-2 access points. The 3800 Datasheet quotes a theoretical maximum throughput of 5.2Gbps when operating in Dual 5GHz radio mode (2 x 2.6Gbps). If you ran two cables to your AP you could use the second ethernet port to create a 2 x 1Gbps LAG. However there is still some debate about whether 2Gbps of throughput is sufficient for a single-radio Wave2 AP.
Some companies may not be willing to invest the time and expense to swap out their copper for fiber or run yet more copper to their APs. The NBase-T standard 802.3bz provides an alternative approach, promising speeds of 2.5Gbps or 5Gbps over Cat5e cabling over 100 Meter runs.

Peter Jones from Cisco is the chair of the NBase-T alliance and presented to us in Tech field day on the new 802.3bz standard and the technology behind it. Cisco terminology for NBase-T-like functionality is ‘MultiGigabit Ethernet’. Currently the Cisco Catalyst 2k, 3K, and 4K switching line have specific models or line cards which support a number of combined UPoE/MultiGig ports. The reason for new hardware is that new digital signal processors (DSPs) are required to achieve the 2.5Gbps Continue reading

Programmable ASICs

I love learning about network hardware, but I’ve always found it difficult to get detailed information on ASICS. We had a great presentation from Dave Zacks on the Cisco 3850 programmable ASIC at the Cisco Live Europe Tech Field Day … Continue reading →

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East West Segmentation With ACI

East/west segmentation is required in the data center to protect backend networks from each other. Segmentation is often implemented using ACLs between VLANS on your core switch. The ACLS are maintained by network or security engineers but define the flows permitted … Continue reading →

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Thoughts on leaving Amazon

Hi All, I left Amazon in late 2015 to become an independent contractor. I took a contract working for a small managed service provider, which was closer to my home and offered a more family friendly schedule. It wasn’t an easy … Continue reading →

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Redistribution of named and tagged static routes

I always name my IOS static routes as a best practise. However I hit a syntax issue last week when I tried to combine the named static with a tag, then redistributing that tagged static route into OSPF. If you have … Continue reading →

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Basic network change control process

Scenario: You are an engineer who runs a managed network on behalf of a customer. Your manager has asked you to create a change control process. Your customer and your manager will measure you only by the uptime or outages they experience, and … Continue reading →

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Network change – who is in control?

Network Change Nothing sparks engineering debate quite as much as ‘network change control’. It’s one of those topics we love to hate. We feel buried by useless bureaucracy. We ask, ‘Why can’t our managers just trust us, instead of weighing us … Continue reading →

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VTY ACL doesn’t block HTTP/S access

I was doing some testing on a 3750X and saw that the http and http servers were enabled. I knew you could apply an ACL to restrict HTTP access, but had assumed that the HTTP security was an optional extra on … Continue reading →

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Link Utilisation Varies By Packet Size

I said to a colleague recently, “you can’t get 100% link utilisation on an Ethernet link”. When I tried to explain myself I wished I could link to a simple blog post with a nice graph. So here’s a quick … Continue reading →

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SPAN Scaling Challenge

I’m facing a mini scaling challenge with Cisco SPAN (Switched Port ANalyzer) session and thought it would be good to share it with you fine folk. SPAN Challenge A 3750X switch is currently SPAN-ing a 10Gbps interface to a 1Gbps egress port. A … Continue reading →

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Four Trouble Ticket Survival Tips

Sometimes the phrase ‘working the ticket queue’ is code for ‘doing meaningless work’. If you find yourself playing whack-a-mole with your ticket queue, then this is the post for you. You should strive to do meaningful work and this post discusses … Continue reading →

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3 Suggestions for Network Automation

Network automation is a hot topic right now. However, many of the automation solutions focus on edge-port provisioning. I can understand why vendors are chasing this niche; port-provisioning is a high-volume and error-prone activity. Network Automation Ideas Port provisioning isn’t the only … Continue reading →

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Network config backups – just the beginning

An emergency switch replacement can ruin your day. However, having network config backups is not enough. Restoring full service may not be as easy as just copying the running configuration from your RANCID CVS repo, or your colleagues hard drive. Restoring the ‘identity’ … Continue reading →

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My top five posts – Nov 2015

I’ve written quite a few posts on this blog, but admittedly I’ve slowed down a lot. I have plans to change that soon, but in the mean time I’ve compiled a quick run down of my top-five popular posts by … Continue reading →

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What about software assisted networking?

I don’t want a software defined network, I want a software-assisted network. I want tools that will help prevent common but straightforward mistakes and make it easier to baseline a network. These tools have to work on real networks. Those messy, brownfield, imperfect … Continue reading →

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Interface descriptions – your last hope

No, I’m not starting a naming war. Not really. I don’t care if you use ! or # or >> or {} to mark your interface descriptions. I don’t care if you use all-caps or lowercase, or if you feel … Continue reading →

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The many ‘modes’ of multimode

Fiber types are differentiated as multimode or single mode. Single mode was always easy for me to understand but I could never quite understand what ‘multimode’ actually meant. I’m written some notes for myself on this topic that I thought I’d … Continue reading →

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Packet pushers podcast – Hardware Resources

It’s been quite a while since I’ve posted here but I wanted to highlight some work I’ve been doing with Greg Ferro and Simon Chatterjee on the Packet Pushers podcast. We recorded a three part series where we dive deep … Continue reading →

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Using IPMI Serial-over-LAN for server consoles

I’ve been trying to learn linux networking and virtualisation using a donated server in a remote lab. The server didn’t have an IP-KVM attached but it did have a working IPMI connection. Not that I’d need it of course; I … Continue reading →

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Is CPU or ASIC responsible for forwarding?

I received the question below from reader Ned as a comment on my 24-port ASIC post and thought that the discussion was worth a post of it’s own. …Would you be able to speak a bit about the actual physical path … Continue reading →

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