Discussion on IWAN

[pgyogeshkumar]

In recent days, I came across to hear about IWANs, although I am not aware of what is the technology and how to configure and use it.

The idea what I got by reading some overview docs is that it

1. Based on the traffic endpoints and type of traffic, it can save the MPLS network bandwidth and route towards alternate path available. 

Why cant the above be achieved through effective routing policies ?

2. I also read somewhere that we can extend MPLS through internet as well. Is this true ? Please confirm.

3. How to configure Iwan and what devices required to configure Iwan and how to use it in enterprise network having MPLS connection

Please confirm for above queries and this will help me to learn on new platform starting from basics.

[Jon Marshall]

1) You can't save MPLS bandwidth by routing policies ie. you need something different to route over.

2) Not sure about this. IWAN is primarily about using the internet for your company WAN although there are variations ie. you can run a hybrid model where both MPLS and the internet can be used.

Perhaps this is what you are referring to ?

3)  You should start by looking at the Cisco design guides which go into detail about what it is and how to use it.

Jon

[pgyogeshkumar]

Thanks Jon Marshall for your time

Thanks for the documents, Will go through those..

Second point is also fine, I was talking about MPLS VPN + Internet connectivity.

I have query on first point, When an enterprise is having MPLS and an Internet connection, The RFC1918 address used in the Organisation will be routed towards MPLS and the rest of the destination (Internet) will be routed towards Internet connection based on default route.

Incase if we need to route traffic towards few Intranet Servers through Internet then, even through Internet also we can create site to site VPN tunnel towards server location and can have specific static route at branch office towards specific server pointing to Internet router as next hop. In this way we can save some MPLS bandwidth I guess. I was telling this in my first point.

So if the above solution works whats the specific benefit of IWAN.. Can you please help me in briefing.. Thanks in advance..

For Configurations and on how to use IWAN, I will go through documents shared by you first..

[Jon Marshall]

You coud use static routes if you wanted but IWAN is about doing all this dynamically.

It uses technologies such as PfR to dynamically route traffic based on traffic statistics and can modify the path based on certain SLAs you specify.

With statics you get none of this.

All of this is covered in the design guide.

Jon

[pgyogeshkumar]

Thank you Jon for your time and help.

I will go through your docs to dive in further

[pgyogeshkumar]

Hi Jon

The link which you shared is not visible in your comment. Can you please share the link once again pls..Not sure how it got disappeared !!

[Jon Marshall]

Here you go -

http://www.cisco.com/c/en/us/solutions/enterprise/design-zone-branch-wan/index.html#~designs

Jon

[pgyogeshkumar]

Hi Jon

I was going through the designs, and confused with NHRP terms and PFR terms

Can I configure PFR and MC in Distribution switches like CAT 6500 series or should I use PFR in Border routers only ?

The tunnel interface mentioned in the design doesnt have any destination mentioned why is that so ? Is  it because for VRF mentioned in tunnel ?

Can I skip NHRP, FVRF, and QOS initially for just to test IWAN in lab and create DMVPN with two wan links directly connected to DMVPN HUB routers ?

What makes the difference and how the HUB and Spoke is defined in DMVPN as I couldnt see that in configurations of this design

Requesting you to please clarify my queries

[pgyogeshkumar]

Hi Jon 

Kindly clarify for above queries.

Mainly clarification required on below query

1. Can I create DMVPN and deploy IWAN in a point to point network please ?

 Thanks in advance