Certain models of DVR are Cloud Enabled .You need not do any port forwarding setup on your Router for Internet view of DVR.
You need to note the 16 digit Serial Number of the DVR & enter the site
Login as Device and under ID enter the serial number to view the CCTV Cameras connected to DVR over Internet.
Watch this demo video :
Cloud Enabled DVR
For Network connections certain models of DVR support 3G DONGLES.
BUSH PLUS DVR 9108I is one such model which is both Cloud Enabled as well as 3G enabled.
Watch this video :
Using a 3G Dongle with a DVR
For availability of BUSH PLUS CCTV items contact :
alselectro 
Where I get this dvr and cctvs adjustable to this dvr in india
Where is get bush plus dvr and cameras in maharashtra