Kentik

JANUARY 24, 2022

Back in the 1990s, NetFlow was introduced on Cisco routers as a means to collect information about IP network traffic as it enters or exits an interface. You can also learn about the protocols in use, the ports being used, the top interfaces, etc. IP protocol. Source port for UDP or TCP, 0 for other protocols.

Application 96

Application IP Address DNS Port 96

Kentik

JANUARY 13, 2021

Send these pings using the Internet Control Message Protocol (ICMP) or TCP to one or any of the devices you believe to be involved. Ping is a utility that’s available on practically every system, be it a desktop, server, router, or switch. Get the Path with Traceroute. Could it be a misconfiguration issue?

Network 114

Network Networking TCP Protocol 114

Kentik

MAY 8, 2023

While redundancy is a significant contributor to network resilience, other mechanisms, protocols, and methods can also contribute to overall network resilience. Many network protocols have been designed to handle different aspects of this process. Let’s highlight some of the primary protocols.

Network 52

Network Networking IP Address TCP 52

Kentik

DECEMBER 8, 2016

Not Just for NetFlow, Kentik Detect’s Analytics Cover All Major Flow Protocols. In networking terms, a “flow” defines a uni-directional set of packets sharing common attributes such as source and destination IP, source and destination ports, IP protocol, and type of service. NetFlow statefully tracks IP packets on a per-flow basis.

Protocol 40

Protocol Port Routers Network 40

Kentik

JANUARY 10, 2022

Or, perhaps one or more of the 10-20 routers in the path needed to reach the destination gets busy for a hundred milliseconds or so. Connect time : Prior to downloading the entire web page, a TCP connection is established between your PC and the application. The use of ICMP vs. TCP or UDP to carry the ping can also be a factor.

IP Address 98

IP Address DNS TCP Application 98

Kentik

APRIL 3, 2023

event(data) duration = float(event) / 1000000 print("TCP retransmit detected (duration: %0.2f For example, to determine latency using traffic generated from probes or by analyzing packets, that traffic would likely pass through routers, firewalls, security appliances, load balancers, etc.

TCP 110

TCP Application Virtual machine Network 110

CATO Networks

APRIL 26, 2016

It lies at the core of how the Internet was built, its protocols, and how service providers implemented their routing layer. There isnt going to be a shiny new router that would magically solve it all. If they are lost along the way, it is the responsibility of higher-level protocols such as TCP to recover them.

Internet 52

Internet Routers MPLS Protocol 52

Kentik

SEPTEMBER 11, 2018

a sequence of related packets) as they traverse routers, switches, load balancers, ADCs, network visibility switches, and other devices. Network elements that support traffic monitoring protocols such as NetFlow and sFlow extract critical details from packet flows, like source, destination, byte and packet counts, and other attributes.

Protocol 66

Protocol Ethernet Network Networking 66

Kentik

FEBRUARY 8, 2016

Designed before the dawn of the commercial Internet, the Border Gateway Protocol (BGP) is a policy-based routing protocol that has long been an established part of the Internet infrastructure. An internal routing scheme so that every router in a given AS knows how to get to every other router and destination within the same AS.

Advertising 49

Advertising Routers Internet Protocol 49

CATO Networks

OCTOBER 30, 2019

Network packets, the protocol data units (PDUs) of the network layer, are often taken for granted by network pros. We all get the concept: to transmit data over a TCP/IP network like the Internet requires the data be broken down into small packets (usually less than 1500 bytes) containing the relevant application data (payload) and headers.

WAN 52

WAN Routers TCP Protocol 52

Kentik

OCTOBER 12, 2021

HTTP is the new TCP. Fifteen years ago, NetOps could start up a packet analyzer and see all kinds of different unencrypted protocols such as FTP, SMTP, POP3, HTTP, DNS, etc. These protocols helped the NPM identify applications. Start up a packet or flow analyzer and make note of the most popular protocol.

Encryption 84

Encryption DNS IP Address Protocol 84

CATO Networks

JUNE 1, 2020

The challenge in the underlying causes of packet loss can be anything from overworked routers to network congestion to software bugs. Proxy TCP Connections Fundamentally, TCP (Transmission Control Protocol) connections inherently add more overhead than their UDP (User Datagram Protocol) counterparts.

Network 52

Network Networking TCP MPLS 52

Kentik

MAY 21, 2019

The Mirai botnet was first discovered back in 2016, but has continued to persist and abuse common vulnerabilities and exposures (CVEs) on IoT devices, including home routers and many other network-connected devices. Vuldb has additional information on the life of this exploit.).

Port 81

Port IP Address Internet Network 81

Kentik

JUNE 7, 2023

They capture detailed information about network traffic, including: Source and destination IP addresses Ports Protocols Packet counts By analyzing these logs, you can gain visibility into the volume, patterns, and characteristics of traffic, such as whether it’s being dropped or incorrectly routed, to identify connectivity issues.

Cloud 97

Cloud Gateway Port IP Address 97

Network Engineering

DECEMBER 11, 2023

We have a block of static IPs facing the public, and have to have a router which points all the traffic to our router/gateway which points all the traffic to the ISP. Right now, all traffic has a static rule to send all traffic to the ISP gateway on the router at the edge going to the hand off. network subnet 10.113.0.0

VPN 52

VPN Port Protocol WAN 52

Kentik

MARCH 13, 2019

A common DDoS mitigation technique is Remotely-Triggered Black Hole (RTBH), which requires extensive pre-configuration of discard routes and/or uRPF on all edge routers. IP Protocol. Flowspec action : Flowspec uses BGP Extended Communities to define actions that routers will take for traffic matching the NLRI attributes from above.

IP Address 49

IP Address Port Routers DNS 49

Kentik

AUGUST 28, 2019

Steaming telemetry uses a push-based mechanism with which data can be transmitted automatically and continuously from various remote sources (such as routers, switches, firewalls, etc.) For example: Transport options: Many choices like TCP, UDP, and gRPC. Encoding options: Choices of JSON, XML, and Google Protocol Buffers (GPB).

Network 16

Network Networking Protocol TCP 16

Kentik

DECEMBER 2, 2015

Here’s how these types of schemes work: The spammer sends a SYN from a spoofed source IP address to TCP port 25 (SMTP) on the target mail server. First, we’ll write a query to get a list of all the hosts in the network that are receiving traffic from remote source port TCP/25 (the traffic described in Step 2 above). AND protocol = 6.

TCP 40

TCP Protocol Port IP Address 40

CATO Networks

OCTOBER 5, 2020

All Cisco products running IOS were impacted, including IOS XR Software, NX-OS Software, and RV160 VPN Router. Even worse was how Cisco handled vulnerabilities Cisco IOS XRs Distance Vector Multicast Routing Protocol (DVMRP) (CVE-2020-3566, CVE-2020-3569). One mitigation suggests rate limiting the IGMP protocol.

Firewall 52

Firewall Protocol SASE Network 52

Kentik

JUNE 19, 2017

This data — flow records or datagrams, depending on the protocol — is generated by network devices such as routers and switches. As traffic passes through the router on its way from the generator to the target, the router collects flow records and sends them to Kentik Detect, our big data network visibility solution.

Routers 40

Routers TCP Network Networking 40

Kentik

SEPTEMBER 20, 2016

In this post we’ll talk about using Kentik’s NPM solution to watch the TCP performance of traffic as reported to Kentik Detect from a Kentik nProbe host agent. TCP is the key. Specifically TCP, which is used in over 90% of network transactions. As an example, we’ll use traffic from Kentik’s own servers.

Network 40

Network Networking TCP Server 40

Kentik

AUGUST 28, 2019

Steaming telemetry uses a push-based mechanism with which data can be transmitted automatically and continuously from various remote network devices (such as routers, switches, firewalls, etc.) For example: Transport options: Many choices like TCP, UDP, and gRPC. The gNMI Protocol. Session Initiation options: Dial-out (i.e.,

Network 52

Network Networking Protocol TCP 52

Kentik

JULY 28, 2021

It isn’t so much that packet loss is a huge problem — TCP and QUIC were engineered in anticipation that lost packets would be inevitable. Latency : Missing packets in connection-oriented protocols such as TCP and QUIC result in lost packets getting resent. Bad hardware (the switch or router port). Overwhelmed router.

Cloud 116

Cloud TCP Routers Protocol 116

Kentik

DECEMBER 18, 2017

So it’s interesting to see that Juniper Networks, at 49.6%, is the leading maker of routers and switches sending flow to Kentik Detect. IP Versions and Internet Protocols. UDP (protocol 17) is down in the number 5 spot with only 3.2% of the traffic, and ICMP (protocol 1) comes in right behind it with 2.7%.

Protocol 40

Protocol UDP port Port TCP 40