NetworkTrafficView is a network monitoring tool that captures the packets pass through your network adapter, and displays general statistics about your network traffic. The packets statistics is grouped by the Ethernet Type, IP Protocol, Source/Destination Addresses, and Source/Destination ports. For every statistics line, the following information is displayed: Ethernet Type (IPv4, IPv6, ARP), IP Protocol (TCP, UDP, ICMP), Source Address, Destination Address, Source Port, Destination Port, Service Name (http, ftp, and so on), Packets Count, Total Packets Size, Total Data Size, Data Speed, Maximum Data Speed, Average Packet Size, First/Last Packet Time, Duration, and process ID/Name (For TCP connections).

Nagios XI is a system and network monitoring application. It watches hosts and services that you specify, alerting you when things go bad and when they get better. Some of its many features include monitoring of network services (SMTP, POP3, HTTP, NNTP, ICMP, etc.), monitoring of host resources (processor load, disk usage, etc.), and contact notifications when service or host problems occur and get resolved (via email, pager, or user-defined method).

With Nagios you can:

A Linux packet crafting tool. Supports IPv4, IPv6 including extension headers, and tunneling IPv6 over IPv4. Written in C on Linux with GUI built using GTK+ and released under GPLv3. Does not require pcap.

Packet crafting and sending one, multiple, or flooding IPv4 and IPv6 packets of type TCP, ICMP, or UDP (or cycle through all three). All values within ethernet frame can be modified arbitrarily. Supports IPv4 header options, TCP header options, and TCP, ICMP and UDP data as well, input from either: keyboard as UTF-8/ASCII, keyboard as hexadecimal, or from file.

IPv6 support includes: hop-by-hop, "first" and "last" destination, routing, authentication, and encapsulating security payload (ESP) extension headers. For those without access to a native IPv6 network, IPv6 packets can be transmitted over IPv4 (6to4).

Packet fragmentation for IPv4, IPv6, and 6to4. Assumed maximum transmission unit (MTU) can be changed if unusual fragment sizes are needed.

IP addresses and port numbers can be randomized.

A configurable traceroute function, which supports TCP, ICMP, and UDP packets with all the features mentioned above.

View packets in hexadecimal/ASCII representation, in both unfragmented and fragmented forms.

All packet settings can be saved to and loaded from file.

IP and ASN delegation functions, including: country name/code search and reverse-search, autonomous system (AS) number search by country and reverse-search,  IPv4 and IPv6 address delegation search and reverse-search.

ARP (IPv4) and Neighbor Discovery (IPv6) for querying a LAN for MAC addresses of local nodes.

Retrieve MAC address and current MTU setting of any attached network interface.

Domain name resolution and reverse resolution.