Question

How many NAT incoming connections can a Cisco VPN 3015 concentrator recieve simultaneously?

Asked by: clarkeyi

Hello

I have a specific question regarding the Cisco 3015 VPN concentrator.
I know it can handle 100 simultaneous incoming connections\Tunnels. But I have been asked how many connectoins it could receive with one NATted IP address coming in to the concentrator?.  Does each NAT connection still count as 1 or would it be infinite?

I had an answer of approx 65000 earlier but not sure if i worded the question correctly which I have hopefully done now

Thanks

Ian

This Question has been solved and asker verified All Experts Exchange premium technology solutions are available to subscription members.

Subscribe now for full access to Experts Exchange and get

Instant Access to this Solution

  • Plus...
  • 30 Day FREE access, no risk, no obligation
  • Collaborate with the world's top tech experts
  • Unlimited access to our exclusive solution database
  • Never be left without tech help again

Subscribe Now

Asked On
2005-03-09 at 07:18:15ID21343758
Tags

3015

,

nat

,

vpn

,

can

,

cisco

Topics

Miscellaneous Security

,

Enterprise Firewalls

,

IPSec Security Protocol

Participating Experts
3
Points
325
Comments
12

Trusted by hundreds of thousands everyday for fast, accurate and reliable tech support.

  • "The time we save is the biggest benefit of Experts Exchange to Warner Bros. What could take multiple guys 2 hours or more each to find is accessed in around 15 minutes on Experts Exchange." Mike Kapnisakis, Warner Bros.
  • "Our team likes having a resource that is more secure than just using Google and most experts using this service really know their stuff. It's nice to look here first versus using Google." Dayna Sellner, Lockheed Martin
  • "Anytime that I've been stumped with a problem, 9 out of 10 times Experts Exchange has either the accepted solution or an open discussion of the potential solution to the problem." Kenny Red, eBay Inc.

See what Experts Exchange can do for you.

Got a question?

We've got the answer.

Experts Exchange has been collecting answers to technology questions since 1996…3 million and counting! If you have a question, chances are we already have your answer.

Screenshot of Experts Exchange Knowledgebase

Need individual assistance?

Our experts are ready to help.

If you can't find the exact answer you're looking for, ask our exclusive community of 50,000 experts. You’ll get a personalized answer from a trusted professional.

Screenshot of Experts Exchange Knowledgebase

Want to learn from the best?

Read articles from industry experts.

Thousands of free tech tips, tricks, how-to’s and tutorials are available in our peer reviewed articles section. See for yourself how smart our experts are, no login required.

Screenshot of an Article

Working on a long term project?

Store your work and research.

Save solutions to your questions, answers you’ve discovered through searching plus helpful articles in your personal knowledgebase for easy future access.

Screenshot of Experts Exchange Knowledgebase

Access the answers to your technology questions today.

Subscribe Now

30-day free trial. Register in 60 seconds.

What Makes Experts Exchange Unique?

Members of the expert community talk about why the experience at Experts Exchange is different than what you will find anywhere else.

Trusted by the world's most respected brands.

image of each brand's logo

Faithfully serving IT professionals since 1996.

Experts Exchange Logo

Try it out and discover for yourself.

Subscribe Now

30-day free trial. Register in 60 seconds.

Related Solutions

  1. VPN && NAT
    Hi. Is it possible to create a VPN connection with a computer with NAT (without access to a gateway) and a diffrent LAN (with access to a gatway)? Then how. Thanks.
  2. Netscreen VPN tunnel with NAT feature not working
    Hi geeks, I established VPN tunnel between Netscreen25 to Cisco VPN concentrator, any body who need configuration parameters can contact me. Problem: FW / VPN ---------- ----------- Internet -----|Netscreen|-----|Mail Server ...
  3. VPN and NAT
    Dear experts. I'd like to setup a VPN connection to my office so I can work from home and connect to network resources, such as file sharing, printers, database and webserver. In my office I have a Windows 2003 Server PC, running most network services. I'd like it to be th...
  4. Nat through VPN tunnel
    I'm trying to figure out the correct way to go about this. I'm more familiar with cisco firewalls. I have a host 192.168.1.5 that I want to nat to 10.10.10.5 to talk to host 192.168.200.5. I can't send 192.168.1.5 because that network already exists on the remote site. Any...
  5. Checkpoint Firewall NAT - VPN Tunnel Cisco
    I am creating a VPN Tunnel with a client to access a SQL server on their end. The setup is as such: Site A (My Location) Cisco VPN Concentrator (for the Tunnel) Checkpoint Firewall (NAT) Private IP scheme 10.0.x.x/20 Site B (client site) Sonic Firewall (tunnel and NAT) Priv...

Free Tech Articles

  1. WARNING: 5 Reasons why you should NEVER fix a computer for free.
    It is in our nature to love the puzzle. We are obsessed. The lot of us. We love puzzles. We love the challenge. We thrive on finding the answer. We hate disarray. It bothers us deep in our soul. W...
  2. SCCM OSD Basic troubleshooting
    SCCM 2007 OSD is a fantastic way to deploy operating systems, however, like most things SCCM issues can sometimes be difficult to resolve due to the sheer volume of logs to sift through and the dispe...
  3. Migrate Small Business Server 2003 to Exchange 2010 and Windows 2008 R2
    This guide is intended to provide step by step instructions on how to migrate from Small Business Server 2003 to Windows 2008 R2 with Exchange 2010. For this migration to work you will need the fo...
  4. Create a Win7 Gadget
    This article shows you how to create a simple "Gadget" -- a sort of mini-application supported by Windows 7 and Vista. Gadgets can be dropped anywhere on the desktop to provide instant information, ...
  5. Outlook continually prompting for username and password
    There have been a lot of questions recently regarding Outlook prompting for a username and password whilst using Exchange 2007. There are a few reasons why this would happen and I will try to cover t...
  6. Backup Exchange 2010 Information Store using Windows Backup
    There seems to be quite a lot of confusion around the ability to backup Exchange 2010 using the built in Windows Backup feature. This stems from the omission of this feature prior to Exchange 2007 s...

Cloud Class Webinars

  1. Avoiding Bugs in Microsoft Access
    Alison Balter takes and in-depth look at avoiding bugs in Access. In this webinar you will learn about using the immediate window to debug your applications, invoking the debugger, using breakpoints to troubleshoot, stepping through code, setting the next statement to execute, ...
  2. Top 10 Best New Features in Visio 2010
    Scott Helmers gives live demonstrations of the top 10 new features in Visio 2010. This webinar will teach you how to create compelling diagrams by adding shapes to the page with a single click, linking the shapes in a diagram to data in Excel (or SQL Server, or SharePoint), ...
  3. IT Consultant Business Secrets Revealed
    Michael Munger, Experts Exchange tech pro and IT consultant, pulls back the curtain on his very successful businesses and answers question on every IT consultant and business owner should know about. He shares secrets on what he did to solve the 5 most common problems in IT, ...
  4. Disaster Recovery and Business Continuity
    Quest CTO, Mike Billon, gives an overview of the steps involved in building a dunamic disaster recovery plan. Through case studies and an examination of software/hardware tooles for monitoring and testing, you'll gain a better understandin of where you are, where you want ...
  5. Organize Your Visio Diagrams with Containers and Lists
    Scott Helmers uses cross functional flowcharts, wireframe diagrams, data graphic legends and seating charts to teach you: how to ustilize all three new structured diagram components in Visio 2010, the best practices for organizeing shapes in previous version of Visio, how to organize ...
  6. How to Us Objects, Properties, Events and Methods in Microsoft Access
    Alison Dalter gives an in-depbth look at objects, properties, events and methods in Microsoft Access. In this webinar you will learn about using the object browser, referring to objects, working with properties and methods, working with object variables, understanding the ...

Join the Community

Give a Little. Get a Lot.

Join the community of experts here and help other tech pros by answering question in your area of expertise. You can earn FREE access to all Experts Exchange's premium features and resources.

Join the Community

Answers

 

by: richrumblePosted on 2005-03-09 at 08:18:30ID: 13497380

Looks like 75 "clientless"

Cisco VPN 3015 Concentrator
The Cisco VPN 3015 Concentrator is designed for small- to medium-sized organizations with bandwidth requirements up to full-duplex T1/E1 (4 Mbps maximum performance), with support for up to 100 simultaneous IPSec sessions or 75 simultaneous clientless sessions. Like the Cisco VPN 3005, encryption processing is performed in software, but the Cisco VPN 3015 is also field-upgradable to the Cisco VPN 3030 and 3060 models.

From http://cisco.com/en/US/customer/products/hw/vpndevc/ps2284/products_data_sheet09186a00801d3b56.html
-rich

 

by: richrumblePosted on 2005-03-09 at 08:30:48ID: 13497529

I think that would be for all clientless connections, not just one nat'd address... cisco can be a pain about these things... I'm sure if you had 76 users all behind a nat, accessing the resource on the other end of your nat if that would count... I think it would...
To clarify

76 Client at company X connecting through the nat'd ip of 1.2.3.4
connecting to your concentrator nat of 4.3.2.1 (which would map over to some server on your lan like 10.1.1.1) once the 76th person tried to connect they'd have reached the maximum.
It keeps track with what is passing in/out of the concentrator to the lan, not how many IP's it sees coming in (which in this example would only be one ip)
-rich

 

by: neteducationPosted on 2005-03-09 at 15:18:11ID: 13501496

Theoretically there is a limit at about 65'000. However the real limit is lower. You can't say an exact number, it's based on the load, the different connections use.

Basically to answer your question: It does not make any difference if the clients are coming in through NAT or not, you still have the same limits as before.

 

by: clarkeyiPosted on 2005-03-09 at 15:33:04ID: 13501590

I am a bit confused. So does this mean the limit is still 100 or nearer 65000?

Cheers

 

by: neteducationPosted on 2005-03-09 at 15:59:32ID: 13501775

if users are doing nothing at all, the limit is 65000.
if the users are doing some work (transfering file, accessing databases and so on) the limit is 100

The limit is not technically implemented, it is the cpu the is doing encryption/decryption that can't handle more.

So for reality use 100 as the value

 

by: richrumblePosted on 2005-03-09 at 16:50:24ID: 13502024

I've found that cisco has hard coded the limits on concentrators. You can open a TAC case to see if they have any more offical offerings, but the literature I've found to be correct in the past with reguard to connection limits. We us 3030's and we've had this very issue.
For IPsec tunnles, even if you have multiple host's behind a nat, connecting to your concentrator, each ipsec tunnel is a session, therfore you can have only 100 ipsec connections, and the source IP does not matter, as there is an authentication method for each tunnel. I've just tried a little example here at home. I have my gateway pc, and another behind it, both are coming from the same ip, I can initiate two tunnels into work, and when I view the concentrator web page I see both sessions from the same source IP and they both count as individual connections.

A pix or router is better suited for doing plain old NAT and PAT functions.
-rich

 

by: clarkeyiPosted on 2005-03-10 at 00:57:39ID: 13504045

Thanks for the advice. I will stick to 100 as the limit.

Thanks

Ian

 

by: clarkeyiPosted on 2005-03-10 at 00:58:36ID: 13504050

Next question How do I split the point for richrumble and neteducation

 

by: neteducationPosted on 2005-03-10 at 01:08:48ID: 13504096

Take one as the accepted answer and the other as "assist" (never done by myself, just seen several times here)

 

by: tmehmetPosted on 2005-03-10 at 03:56:09ID: 13504991

my experience is that you must not take actual figures from vendors seriously, you must test it to find out for yourself.

if you are about to make a decision for your business, the only way to be certain it to get it into your labs or go to cisco labs and make them demonstrate it.

Once you start trying to prove it, you will find that the vendors start to release practical numbers during the tests for different scenarios.

Cisco have got better but they do like most still put some spin on their figures.

20120131-EE-VQP-002

3 Ways to Join

30-Day Free Trial

The Experts

98% positive feedback on 31,087 answers since March 2000. angeliii is a Microsoft Most Valuable Professional for his work with MS SQL Server & Develoment.

He has also proven his knowledge of Visual Basic Programming, PHP Scripting and Oracle Databases.

The Experts

97% positive feedback on 10,752 answers since July 2000. lrmoore has more than 18 years experience in the networking industry.

The six-time Mircosoft MVPs specialties include firewalls, virtual private networking, and network management.

Testimonials

"...and excellent source for support... Kind of like having your very own IT dept." Electriciansnet

Testimonials

"I was apprehensive at signing up at first. However... it has already made my life as an IT administrator much easier." JaCrews

Testimonials

"WOW! You guys have great, active, and knowledgeable people on here." moore50

Business Clients

Business Clients

In the Press

"If you’ve got a question... Experts Exchange can supply an answer.”

In the Press

"...an invaluable aid for both IT professionals and those who require tech support."

In the Press

"where IT professionals provide quick answers on just about any topic"

Business Account Plans

Loading Advertisement...