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rafaelbn_305907's avatar
rafaelbn_305907
Icon for Nimbostratus rankNimbostratus
May 06, 2018

ssldump first connection doesn't seem to transfer any data

Hello Devs! When a client connects using IEv11, the first and second TLS connections does not seen to transfer any data. The application is working just fine. I'm just curious about this... Here ...
application delivery
BIG-IP
LTM
security
rafaelbn_305907's avatar
rafaelbn_305907
Icon for Nimbostratus rankNimbostratus
May 07, 2018

I did a tcpdump and I can see that when I try to connect through a browser (IE11), the browser establishes 4 connections and do 4 client hellos.

 

 

But when I connect through "openssl s_client -connect 192.168.1.43:443" and do a "GET / HTTP/1.0" I get the same page but only one connection:

 

 

I uploaded both captures to cloudshark:

 

Connection from Linux box (only one SSL client hello) - https://www.cloudshark.org/captures/63c678837a25

 

Connection from IE11 (4 SSL client hellos) - https://www.cloudshark.org/captures/f6924bd9ecaa

 

Thanks! Rafael