Saw this interesting article on BF4central that shows the netcode problems this game has or had. The article is from Nov 5th and primarily focuses on the PC version of that timeframe. It's had patches since and netcode has been improved.
Of course that's the over a month old PC version. Considering these issues that the Xbone/PS4 version is having with broken server browsers, freezes everywhere, corrupt saves..blah blah blah etc, I have a big feeling that these issues the PC version had are still in the console version.
I have my PS4 hooked up via Ethernet to a 45mb down/ 12mb up ADSL2+ connection to a router that is DMZ'd to my PS4's IP Address with port forwarding and UPnP enabled just to help as well maximising my connection.
BF4 for me in infantry combat is a overall bad-meh experience. It's bizarre really. In a one on one encounter i'll lose most of those encounters yet generally i'd have the enemy's health down to like 3%.
There are times where i'd literally shoot the enemy with like 5 bullets and get turned on. This happens far too often to the point that it's now becoming too difficult to play.
And before you say "oh you might just be bad?"
My 360 stats are lower due to playing MW3 more and only got into BF3 much later on. I play on my own too. So I already know i'm not a bad player and BF4 in gameplay is essentially BF3 but more sluggish and slow. (despite playing it on consoles at 30fps and 60fps)
Here's my BF4 stats for reference http://bf4stats.com/ps4/sean007s
I'm obviously struggling compared to my days on B. And personally I think it's the netcode as the main culprit. Like I said, there are times where I literally am just gobsmacked at why I didn't kill the enemy when I know well that I should have.
I found crazy lag or hit detection issues while sniping that I just have no idea what the hell is happening. Like clearly seeing my bullet go through the enemy without any hitmarkers at all which in BF3, generally it'd be a hitmarker or kill, i loved my M98B in that game and used it alot, it's my most used weapon on the 360 version.
I find it hard to explain this, but all I know is, I should be killing enemies despite putting rounds upon rounds into them and they just turn on me. This isn't even COD levels of bad, it's literally worse.
The article above demonstrates the issues i've had although not as bad as some of the videos inside. Godamn.