Issues connecting to remote host

Hi Comcast support forum,

I'm having issues connecting to a series of hosts from my Comcast Business Class connection. I do not have that problem from two different internet connections.

Let me explain the issue more in depth:

I tried connecting to the host 176.57.128.228 using a proprietary service which failed. The service claimed it cannot reach the specified host.

I checked if I have basic IP connectivity using ping, which however timed out. Knowing that some hosts might silently drop ICMP ping packets I ssh'ed into a different machine on a different network (in fact geographically located quiet close to the machine running the service I tried to connect to) and pinged the host in qustion from there. This time I got a response.

I ran a traceroute from my local Comcast connection to the host in question, but the traceroute got stuck at a certain router (dtag.ociris.com) which I will talk a bit more about in a second. The traceroute form the machine I ssh'ed into did successfuly passed that router, but got stuck on a later host. I suppose some kind of firewall drop. However, I was always able to ping the host I can't reach from my Comcast account. 

I decided to check who the IP adress dtag.ociris.com resolves to is registered to and try to get in contact with them. The IP address 80.95.152.123 is registered to a German company link11. I shot an email to info@link11.de and explained my issue. To my suprise I did receive an answer stating that the issue was fixed.  However I continue to have the exact same problem.

I hope you guys have a better guess at what's broken, how to fix it and who to get in contact with to fix it. Please let me know!

- Daniel