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MichaelM's avatar
Icon for Altostratus rankAltostratus
May 22, 2015

speed issue with VPN access

Hi all,


We're using VPN access to internal network via APM access profiles and LDAP authentication. [F5 VE 11.4.1 - main tasks LTM (http-to-https VS redirect and SSL offload), device is not overloaded] Solution works fine but some users complaining about massive speed issue.


To investigate the issue I set up a BIG-IP Edge Client on Win7 test box via ADSL connection ( latency=29ms,down=12Mbps,up=0.9Mbps). As soon as I connect via VPN results showing a massive drop ( latency=461ms,down=0.55Mbps,up=0.37Mbps).


I have to admit that I don't have a detailed overview of the internal network but I know that Internet traffic passes through a proxy. Therefore I tried to 'eliminate' network topology and proxy by using "LAN Speed Test (Lite)" by Totusoft transfering test file to a share on a Win2008R2 box just two 'hops' behind the F5s internal subnet. The tool confirmed the bad throughput showing 0.85Mbps. Edge Client showed a throughput between 2.3Mbps (inbound) and 860Kbps (outbound) during the transfer (best values during write/read).


It appears that the VPN is throttling the bandwidth so much but how can I find out for sure that it is the F5 VPN? Do I need to optimize the (network) access profile? We're not using a Client Traffic Classifier to limit the traffic.


Any hint is much appreciated. cheers


4 Replies

  • Hi,


    I dont know if my opinion goes in the same way that your case, but I experience 2 behaviors that I want to share (I don't have the solution right now):


    1) VPN clients consumes a high bandwidth 2) It runs poorly in slow internet connections (ADSL 1Mbps), at the point of not loading application through it (for example Outlook in Office 365). With the same connection a Cisco IPsec client works fine.


    I have cases opened for these issues that maybe are related. I will let you know when I obtain a solution.


    Best regards


  • Hi F5 Support,


    I have also this issue, VPN Tunnel speed up to 100kbps only. I'm using F5-VE Version BIGIP-, VPN via APM(Network Access).


    Is this normal?


    thanks in advance. /emille


    • xXhd1912Xx_1953's avatar
      Icon for Cirrus rankCirrus

      Similar issue with VPN tunnel choking off link speed. F5 has yet to acknowledge this issue. I have tested this on a local lan with 11.6.1 and 12.1.2. I setup minimal policies and tweaked every TCP setting with no improvement.