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Category Archives for "Packet-Forwarding.net"

Snippet: The story of the EFP

For a while now, the concept of EVC’s (Ethernet Virtual Circuits) and EFP’s (Ethernet Flow Points), has eluded me.

In this short post, i will provide you with a simple example of a couple of EFP’s. In a later post i will discuss the MEF concept of EVC’s.

As always, here is the topology i will be using:

topology

Its a very simple setup. R1 connects to R2 through its G1 interface and connects to R3 through its G2 interface.

On R2 and R3, we have the very common configuration of using subinterfaces for the individual Vlan’s in question. Namely Vlan 10 for the connection between R1 and R2 and Vlan 20 between R1 and R3.

Here is the configuration of R2 and R3:

R2#sh run int g1.10
Building configuration...
Current configuration : 98 bytes
!
interface GigabitEthernet1.10
encapsulation dot1Q 10
ip address 10.10.10.2 255.255.255.0
end

R3#sh run int g1.20
Building configuration...
Current configuration : 98 bytes
!
interface GigabitEthernet1.20
encapsulation dot1Q 20
ip address 10.10.10.3 255.255.255.0
end

Now on R1 is where the “different” configuration takes place:

R1#sh run int g1
Building configuration...
Current configuration :  Continue reading

Practical DMVPN Example

In this post, I will put together a variety of different technologies involved in a real-life DMVPN deployment.

This includes things such as the correct tunnel configuration, routing-configuration using BGP as the protocol of choice, as well as NAT toward an upstream provider and front-door VRF’s in order to implement a default-route on both the Hub and the Spokes and last, but not least a newer feature, namely Per-Tunnel QoS using NHRP.

So I hope you will find the information relevant to your DMVPN deployments.

First off, lets take a look at the topology I will be using for this example:
Topology

As can be seen, we have a hub router which is connected to two different ISP’s. One to a general purpose internet provider (the internet cloud in this topology) which is being used as transport for our DMVPN setup, as well as a router in the TeleCom network (AS 59701), providing a single route for demonstration purposes (8.8.8.8/32). We have been assigned the 70.0.0.0/24 network from TeleCom to use for internet access as well.

Then we have to Spoke sites, with a single router in each site (Spoke-01 and Spoke-02 respectively).
Each one Continue reading

1st Attempt – No Dice

So I just got back from my first attempt at the CCDE practical, and unfortunally I didnt pass it.
It was a very different exam than the CCIE and it takes a little while to become used to the interface and exam style.

I started my journey to London on the 30th of August and right off the bat it started out badly with me getting an eye infection in one eye. By the end of the day it had spread to my other eye. Not really what you want or need going into an exam which is heavy on the reading part.

However, it was awesome meeting some of my study buddies from our Slack group! We had a great meal and a few good beers! – Time to call it a night.

The exam has been documented elsewhere, so i wont spend much time on it here. Suffice it to say its a difficult beast ?

I only used 5.5 hours of my 9 hour slot, and i just wanted to get out of there and rest my eyes to be honest.

I departed London September 1st and im now back at work. Much the wiser however.

I Continue reading

Cisco Live US! 2016

I am fortunate enough, to be able to goto Cisco Live US! again this year.
Last year was such an experience, that my hopes are really high for this year as well.

I will be arriving on Friday the 8th and leaving on the 15th. Not a long stay this time, but it was what my boss could arrange for.
Again this year I will be bringing my better half, so she can experience the city and hopefully we’ll get a few hours of sightseeing in between commitments.

One of the things that im really looking forward to, is meeting up with friends and peers. This year is a bonus for me, as I get to say Congratulations to my friend Daniel (lostintransit.se) in person and not just on the phone, on passing the CCDE practical exam!

Also, a first for me, will be meeting up with Darren (mellowd.co.uk). We have been talking for a long time on twitter, mail and webex and im really looking forward to meeting him in person.

When we get closer to the event, I will be posting my Cisco Live! schedule here.

If you happen to be Continue reading

GETVPN Example

A couple of weeks ago I had the good fortune of attending Jeremy Filliben’s CCDE Bootcamp.
It was a great experience, which I will elaborate on in another post. But one of the technology areas I had a bit of difficult with, was GETVPN.

So in this post a I am going to setup a scenario in which a customer has 3 sites, 2 “normal” sites and a Datacenter site. The customer wants to encrypt traffic from Site 1 to Site 2.

Currently the customer has a regular L3VPN service from a provider (which is beyond the scope of this post). There is full connectivity between the 3 sites through this service.

The topology is as follows:

Topology

GETVPN consists of a few components, namely the Key Server (KS) and Group Members (GM’s), which is where it derives its name: Group Encrypted Transport. A single SA (Security Association) is used for the encryption. The Key Server distributes the information to the Group Members through a secure transport, where the Group Members then use this information (basically an ACL) to encrypt/decrypt the data packets.

The routing for the topology is fairly simple. (See Routing Diagram) Each client as well as the KeyServer Continue reading

February – A busy month indeed!

Wow, what a busy month this has been!

So I started my new job on February 1st and thus far, everything has been really great.
My new coworkers are very friendly and helpful.

I’ve spent the better part of february, trying to get to grips with the SP network I will be focusing on from now on. Im still not where I want to be yet, but im getting there. One of the guys I will be working very closely with, started cleaning up the network when he was hired 9 months ago and he’s done a really great job with what he’s had to work with.

There are still some work to be done however, which is the very reason they have hired me and another very good friend of mine. A well run network is a dynamic beast which needs to be tamed. On top of that, the company growth has been around 30% a year, so alot of structure and processes needs to come with that growth, which is where I can really make a difference.

I’ve also had the good fortune of being selected as a 2016 Cisco Champion, which was a very nice surprise. I Continue reading

Doing right in the VAR role!

This post is my follow-up on a recent discussion on twitter.

Working for a VAR (Value Added Reseller) is not always the glamours life some make it out to be.

Working as a consultant, what you are really doing, is being the CEO of your own service company.
What you are selling, is basically your own services. The fact that your paycheck is being signed by someone else doesnt/shouldnt really matter.

The customer is building a relationship with you, as much as the company you are working for.
On top of that, you are continually building rapor in the networking world, so in my opinion, I would rather leave the customer with a good solution, rather than having to stick with the insane budgets that sales people end up shaving a project down to, just to get the contract.

So what can you do to create the outcome that is beneficial for all parties concerned (The customer, Your employer and yourself)?

Well, what I have tried in the past, is try and emphasize the importance of leaving the customer with the right solution based on his/her requirements and constraints. This discussion should involve both the technical side of things, as Continue reading

Passed the CCDE written. Now what?

I was fortunate enough to finally pass the CCDE written exam yesterday morning.

That begs the question of “Now What?”

Well, I will spend a couple of days putting together a study strategy, based on where I am now compared to where I need to be in order to pass the exam. As it looks now, I am probably going for a fall 2016 exam date. That gives me enough time to settle into a new job with everything that entails.

It also means that I will need to spend 2-3 hours of study per day (some weekends more than that), with a combination of watching Cisco Live 365 videos and reading CVD’s/Books.

On top of that, my good friend Daniel Dib and I, along with hopefully a few others will have some design discussions using Webex. We have been told its really important to iron out different design ideas with other people. Especially if we can get a group together with people from different areas of expertise (Datacenter, Service Provider, Enterprise etc.).

Alas, an update to this story will come shortly! :)

Take care!

Time for change

Its time for a change!

It was a tough decision, but i’ve decided that I need some new challenges in my professional life. To that effect, i’ve quit my old job and joined a different VAR/SP where I will be working in a skilled team of network engineers.

My duties will include maintaining and expanding a growing MPLS network, with all the services one can build on top of such a beast. Along with that, I will be attached to large enterprise customers, helping with design and implementation.

The new job is very supportive of my effort to go after the elusive CCDE certification, which was a big part of my decision as well, so expect more updates in that direction!

I’ve had some great years with awesome coworkers, but I have great confidence in the coming years as well!

Finally, a big thanks to my family and friends for supporting me through this decision process!

/Kim

Why Cisco?

Why do i keep focusing so much on Cisco, when there are clearly alot of different vendors out there with similar products and technologies?

There are several reasons for this.

1) I began the professional part of my networking career with Cisco.
2) Cisco has a proven track record when it comes to education and learning.
3) Even though not always the best match for all use-cases, Cisco is a big player in almost all areas of networking.
4) The networking opportunities provided by Cisco is by far the best of what ive seen. Take for example the Cisco Learning Network.
5) Cisco Press is really awesome in my opinion. They have alot of really high quality books out there.
6) Great opportunities to interact with the company. By this i mean to participate in programs like Cisco Champions and different SME (Subject Matter Expert) related activities.
7) Cisco documentation is not perfect, but its hands down the best I’ve seen across multiple vendors.
8) And ofcourse Cisco Live! :)

That being said, recently i have begun to take a more neutral look at technologies. The reason being, that in this day and age, proprietary technologies become less prefered than open Continue reading

The case for lifelong learning.

People often ask me why i keep studying and when i will be “done”.
To me, this type of question seems odd, because i am committed to lifelong learning.

I am of the opinion that going through life without learning something all the time would be a life wasted. I think this goes back to the early explorers. Discovering new things, whether it be a new continent or simply a piece of knowledge really excites a certain type of people.

I am by no means comparing myself to these great explorers, but i understand what drove these legendary people to do the things they did, whether it be Columbus or more recently modern day astronauts.

My studies, whether they be in the field of networking or more personal related, will continue until the day i leave this crazy world.

There so much information and knowledge thats readily available in our day and age, that i would find it hard to simply ignore it and just lean back and say: “thats it, im done!”.

As I write this post, its about 6am in the morning. Part of my morning ritual is getting to the office early and spending some time Continue reading

My first Cisco Live!

Even though im still in San Diego, Cisco Live! US 2015 is but a memory.

But what a memory it is! It being my first time attending a Cisco Live conference, I didn’t really know what to expect.

What I was met with, was a conference full of really sharp and nice people. The conference staff was very helpful and polite and really made an impression on me, from the time I first stepped onto the pavement outside San Diego convention center.

We (I brought my better half to the US) arrived very late on saturday, so after a good nights sleep I took the bus to the convention center to register and pick up the first piece of swag, the famous Cisco Live bag.

One of the great benefits of attending the conference was meeting with my good friend Daniel Dib (from lostintransit.se). I hadn’t seen him since January, so it was really cool to meet up with him during the week.

On Monday Daniel and I attended a session together, but most other sessions I went to alone. For the record, I paid for this trip out of my own pocket, so I didn’t have any co-workers Continue reading

MPLS VPN’s over mGRE

This blog post outlines what “MPLS VPNs over mGRE” is all about as well as provide an example of such a configuration.

So what is “MPLS VPNs over mGRE”? – Well, basically its taking regular MPLS VPN’s and using it over an IP only core network. Since VPN’s over MPLS is one of the primary drivers for implementing an MPLS network in the first place, using the same functionality over an IP-only core might be very compelling for some not willing/able to run MPLS label switching in the core.

Instead of using labels to switch the traffic from one PE to another, mGRE (Multipoint GRE) is used as the encapsulation technology instead.

Be advised that 1 label is still being used however. This is the VPN label that’s used to identify which VRF interface to switch the traffic to when its received by a PE. This label is, just as in regular MPLS VPN’s, assigned by the PE through MP-BGP.

So how is this actually performed? – Well, lets take a look at an example.

The topology I will be using is as follows:

Topology for MPLS VPN's over mGRE

Topology for MPLS VPN’s over mGRE

** Note: I ran into an issue with VIRL, causing Continue reading

Overwhelmed – CCDE

I am preparing for the CCDE written exam, which I have coming up at CLUS.

There are so much material to go through, both to read as well as watch CL presentations, it can be a bit overwhelming at times.

So if you are thinking about going down this path, learn how to speed-read :)

Just under a month until we leave for the US. We are looking very much forward to the break!

Just a quick thought for the day!

Cisco Live US 2015 – Session Schedule

This is my current schedule for the Cisco Live US 2015 event.

Most are related to my CCDE studies and a few are with technologies and products that im interested in in general.

Monday:
08:00 – 09:30 BRKSAN-2101 FCoE for small and mid size enterprises.
10:00 – 12:00 BRKCRS-2031 Enterprise Campus Design: Multilayer Architectures and Design Principles
13:00 – 15:00 BRKARC-2001 Cisco ASR1000 Series routers: System and Solution Architectures
15:30 – 17:00 GENKEY-1001 Cisco Vision Keynote

Tuesday:
08:00 – 09:30 BRKRST-2124 Introduction to Segment Routing
13:00 – 15:00 BRKSPG-2210 Designing Service Provider Access Networks
15:30 – 17:00 BRKDCT-2049 Overlay Transport Virtualization

Wednesday:
09:00 – 12:00 CCDE Written Exam
13:00 – 15:00 BRKRST-3363 Routed Fast Convergence
15:30 – 17:00 BRKRST-2338 ISIS Deployment in Modern Networks

Thursday:
08:00 – 09:30 BRKMPL-2333 E-VPN & PBB-EVPN: the Next Generation of MPLS-based L2VPN
10:00 – 12:00 BRKRST-2311 IPv6 Planning, Deployment and Troubleshooting
13:00 – 14:30 BRKRST-2044 Enterprise Multihomed Internet Edge Architectures
15:00 – 16:00 GENKEY-1004 Guest Closing Keynote: Mike Rowe

Cant wait :)

Cisco Live US – 2015

I will be attending this year’s Cisco Live US in San Diego!

This is my first Cisco Live, so I dont really know what to expect. There are alot of great sessions that I want to attend (if they are not already full), and I will be posting my week here when i have my sessions down.

If you want to connect for a coffee or a chat, feel free to drop me a mail/tweet, and im sure we can figure something out!

See you in San Diego!

Unified/Seamless MPLS

In this post I would like to highlight a relative new (to me) application of MPLS called Unified MPLS.
The goal of Unified MPLS is to separate your network into individual segments of IGP’s in order to keep your core network as simple as possible while still maintaining an end-to-end LSP for regular MPLS applications such as L3 VPN’s.

What we are doing is simply to put Route Reflectors into the forwarding path and changing the next-hop’s along the way, essentially stiching together the final LSP.
Along with that we are using BGP to signal a label value to maintain the LSP from one end of the network to the other without the use of LDP between IGP’s.

Take a look at the topology that we will be using to demonstrate this feature:

Unified-MPLS-Topology

In this topology we have a simplified layout of a service provider. We have a core network consisting of R3, R4 and R5 along with distribution networks on the right and left of the core. R2 and R3 is in the left distribution and R5 and R6 is in the right hand side one.

We have an MPLS L3VPN customer connected consisting of R1 in one site Continue reading