Since the update to 6.13 I have quite big trouble with the speed of sstp-connections. So I made several tests the last days but I can’t figure out how I could make it work and it really seams to be a correlation with the software version.
I've drawn the layout in the file attached, so to sum it up, the main site has a VDSL-connection with 50mbit down and 10mbit up and the client site has ADSL with 16mbit down and 2mbit up.
The issue is the same with different client sites but I tested the different configurations only at one site. On both ends there's a Fritzbox 7490 DSL Router as also the phone system is running over VoIP and the configuration is fixed in these boxes.
On the main site there's a 1100AHx2 and I installed a x86-machine on the client side as I thought it might have something todo with performance... but this seems not to be the issue.
I also tried to lower the MTU by mangle the SYN-packets down in stept to values that shouldn't definitely be fragmented. BTW. the MTU between the sites can be 1492 without fragmentation.
So, with version 6.12 the speed of the link (main-site > client) is about 6Mbps, what's maybe less than it could be but that's fine. (see wan.jpg a)
That's when using Mikrotik on both ends of the VPN and a Windows 7 machine behind the Mikrotik Client. (See layout A).
When I now switch both Mikrotiks to 6.13 (or 6.14rc) I get result about 1500kbps (like shown in file wan.jpg b) and that's really too less to work with.
If I know replace the Client Mikrotik Router with the Windows 7 PC directly (layout B), though connecting with the Windows machine by Microsoft-SSTP-Client to the RB1100AHx2 that's working pretty well and faster. It's about 6.5Mbps with Version 6.12 (wan.jpg c) and about 4.5Mbps with Version 6.13 (wan.jpg d). So the effect that 6.13 has on the speed is much less with the Windows SSTP Client but still definitely to see.
The next setup was to replace the WAN-Link with a 100mbit LAN Link, so there won't be any issue at provider side I can't see (Layout C & D). And in fact it's really faster but the difference is again quite big.
While I get a speed of about 23Mbps using Mirkrotik at both ends with version 6.12 (lan.jpg a) I only get less than 8Mbps with version 6.13 (lan.jpg b).
Now again, replacing the client Mikrotik with the Windows SSTP Client I get way better results. (Layout D)
With version 6.12 I get about 73Mbps and with version 6.13 I get about 86Mbit... That's both fine and don't differ too much. (lan.jpg c/d).
As there are issues with SSTP in Version 6.12 I'll have to use 6.14 in future (connection drops that should be fixed in 6.14).
So I'd appreciate any help finding out what's making the WAN-SSTP-Link so slow with 6.13/6.14rc.
@Mikrotik: Might it be possible to see/know what change for 6.13 could be the cause for this and to fix it in a 6.14rc-version to test?
I'd be happy to give more test result as it's needed.
Thanks a lot for help!!
You do not have the required permissions to view the files attached to this post.