Please make more videos on integration like metadata api

Very nicely explained.

what if external system is using VPN proxy. as we know that salesforce send callout direct from Salesforce server I can't use my VPN or Proxy so How can I do that? it will through this Error : System.CalloutException: Unable to tunnel through proxy. Proxy returns "HTTP/1.1 503 Service Unavailable"

very informative video. Please make videos on other types of integrations also.

Sir how did you changed the Salesforce favicon in your org?

if we are using name credentias will it run automatically every time and get session id whenver we make callout ?

When will you upload part 3?.. Very Nice Content.