Some Random Visio diagram

Below, We have some visio diagrams we have done for customers.

This first design is a customer mesh into a couple of different data centers. We are referring to this as a switch-centric design. This has been talked about in the forums and switch-centric seems like as good as any.

This next design is a netonix switch and a Baicells deployment.

Design for a customer

Networking foundations

In an article earlier today, I wrote about certifications and the ISP.  The biggest area I see folks go wrong when it comes to networking is having a good understanding of design. One of the analogies I like to use is building a house.   You have several key roles when you build a house.  These can be directly applied to the networking world.

The first is the Architect. Everything starts with this person or team’s vision. The Architect lays out the design and how the network will function. This person needs a wide variety of skills.  They know the product lines they are supporting, they know how these products fit into the overall vision of the network, and they know the limitations of what they are working with, to name just a few of their many skills. These are your CCIE and higher level CCNP folks in certification terms.  They have enough breadth of knowledge to see the entire picture.  Not just what the device in front of them can do. A network architect would know that a certain wireless CPE does not fully support a VPLS tunnel, and would either recommend not using that equipment or come up with a workaround to implement it into the network, if in fact, they were using VPLS.  Many large companies have Architects who implement and validate network designs. These are then pushed to the next group of folks to implement.

The “tradesmen” or “tradeswomen” are the ones who actually implement the designs around the Architects blueprints for the network.  Just like a house who has carpenters, brick layers, and roofers, so do you have folks who know wireless, routing, security, and other disciplines.  These are the folks who can make the machines do what they want them to do. They work off the blueprints to actually make the network talk and function according to the Architects design. these are your CCNA and CCNP level folks. These folks know the equipment configuration in and out.  They are the most responsible for making things work, and knowing how to make it work. The more experienced of these folks typically collaborate with the Architects to provide expert opinions on the latest features of the equipment they are implementing or any limitations of the equipment.

Many folks working in the ISP world wear multiple hats at the same time.   There is nothing whatsoever wrong with this.  You just have to know the limitations of yourself and the things you have to work with. I see multiple illustrations of this on a daily basis. Clients take a router and make it do BGP, OSPF, PPPoE termination, firewall rules, and other things.  Sometimes this is a budgetary thing, maybe just a lack of understanding, or it can even be a sales hype thing. however, not having an understanding of the design and architecture of a network can be costly.

Anyone can build a house. Go to the lumberyard and get some materials, some tools, and watch a few YouTube videos. Bam you are set.  That will probably work until the first time it rains, or it gets cold. Then you are wondering where your design went wrong.  Using plastic on your roof sounded like a good idea until the wind ripped it.  Same can be said in networks.  Start and always have design considerations in mind.  Not just design, but how individual components are best used in that design. Then rely on the tradesmen  to implement them.  You might be one and the same, but don’t wing it as you go.

Modular advantages

Several of you have heard me talk about modular network design. There are five distinct advantages of a modular network design.

You can upgrade pieces easier than all-in-one devices. Being able to upgrade a certain module for that big new client might mean the difference between being able to do it in 10 days instead of 30.

You can avoid single points of failure. You are not depending on “big iron” for everything. You have multiple modules as a part of your design.

If routers, switches, access points, or whatever are doing less then you get better performance out them. CPUs are dedicating more time toward less processes. This results in better performance. Routers that are doing just BGP are able to process route tables better than ones doing stuff like OSPF or radius.

You are less dependent on certain vendors, or product families. Instead of having some big router that does BGP, OSPF, and other functions you can have a modular design where a router does, lets say, just BGP. Now you have more choices in hardware because it might not. This allows you to try out newer products or new product features.

5.Easier to maintain
Doing software upgrades on a modular devices, which is doing less things, means bugs and interoperability things don’t happen as often. Every piece of code has bugs. If the device is doing 5 tasks instead of 15 then the chance of a bug affecting the device is less. It also allows you to compartmentalize certain parts of the network.