Total 9 Blogs

Created by - Stanley Avery

IPv6 Address Types

There are several different IPv6 address types, each with its own unique properties. In this blog post, we'll explain the different types of IPv6 addresses and give examples of how they can be used. So, if you're interested in learning more about IPv6 addressing, keep reading! What is IPv6 Address? Why do we need it? The Internet Protocol (IP) address is a unique identifier assigned to every device connected to the internet. It allows for communication and data transfer between these devices. The current version in use, IPv4, can support a maximum of 4.3 billion addresses. However, as more devices are added to the internet – particularly with the rise of the Internet of Things – this limit has been reached and exhausted. This is where IPv6 comes in. It can support significantly more addresses – 340 trillion trillion trillion, to be exact – allowing for continued growth and connectivity on the internet. In addition, it offers improved security measures and better network management capabilities. Overall, IPv6 is necessary to accommodate the increasing number of devices connecting to the internet and ensure smooth communication between them. On the other hand, there are a couple of IPv6 address types you should know. IPv6 Address Types When it comes to IPv6 addressing, there are three distinct types: unicast, anycast, and multicast. Let's talk about these IPv6 address types separately: IPv6 Address Type #1: Unicast In IPv6, the unicast address is used to identify a single network interface. Each node on an IPv6 network has at least one unique unicast address, which can be either manually configured or automatically generated using stateless address autoconfiguration. Unicast addresses are also divided into various categories based on their intended use, such as global unicast addresses for communication across multiple networks and link-local unicast addresses for communication within a single network. IPv6 Address Type #2: Anycast In anycast, a single IP address is assigned to multiple devices, with traffic being routed to the nearest device. This allows for increased efficiency and redundancy, eliminating the need for separate IP addresses for each device and offering backup options if one device fails. Anycast can be particularly useful for services such as DNS servers, as it allows for faster response times and improved reliability. IPv6 Address Type #3: Multicast Multicast addresses allow for a single packet to be sent to multiple recipients simultaneously, unlike unicast, which sends data to one recipient at a time. This can be useful in situations where a group needs to receive the same information, such as in-network meetings or online classes. In IPv6, multicast addresses use the prefix FF00::/8 and can have up to eight groups of four hexadecimal digits each. Final Words If you are looking for more information on IPv6 address types or want to learn about networking in general, our courses have lots of helpful content for you. We offer a range of services, from teaching you the basics of networking to helping you design and implement a network that meets your specific needs. Contact us today to get started!

Published - Sun, 30 Oct 2022

Created by - Stanley Avery

PPPoE vs DHCP

Internet networking can be a confusing topic, but it doesn't have to be. In this blog post, we'll break down the differences between PPPoE vs. DHCP so you can understand which one is right for your needs. We'll also explain how these technologies work, so you can make an informed decision about which one is best for you. Read on to learn more! PPPoE vs DHCP: What are they? Why do we use them? When setting up a network, one must consider the various protocols for connecting devices to the internet. One of the most common comparisons in the networking world is PPPoE vs. DHCP. They might be confusing at first glance, but when you read this article on PPPoE vs. DHCP, you will better understand these two terms. Let's start with their descriptions, shall we? PPPoE: What is it? PPPoE, or Point-to-Point Protocol over Ethernet, is a communication protocol commonly used for internet access. It functions by encapsulating PPP frames within Ethernet frames, allowing for more efficient transmission and better performance. PPPoE can be used for both internet access and virtual private networks (VPNs).  It helps to establish a secure connection between the user's device and the Internet service provider (ISP), allowing for more efficient use of network resources. PPPoE is frequently used in DSL connections and for high-speed wired Internet such as fiber optics. While PPPoE is not required for Internet access, it can provide additional benefits such as authentication and encryption, resulting in a more reliable connection. Additionally, PPPoE can support multiple users on the same physical connection, making it a popular option for residential and business internet plans. DHCP: What is it? DHCP, or Dynamic Host Configuration Protocol, is a communication protocol used on a network to assign devices a unique IP address. This allows for easy communication between devices, as well as the ability for users to join or leave the network without interrupting its functioning. A network's DHCP server handles the process of assigning, managing, and renewing these IP addresses. As each device connects to the network, it requests an IP address from the DHCP server and is assigned one from a pre-determined pool.  The main benefit of this system is that it removes the need for manual configuration of each device's unique IP address. Without DHCP, connecting to a network would be much more difficult and time-consuming. So next time your internet runs smoothly, thank your DHCP server for making it happen! PPPoE vs DHCP: What are the main differences? When connecting devices to a network, there are a few different methods that can be used: PPPoE vs. DHCP. While both provide the ability to assign an IP address to a device, they each have their own distinct characteristics.  PPPoE needs to be configured correctly before a user can connect to the internet, while DHCP is much simpler and only requires plugging in. Basically, DHCP does away with the headaches PPPoE gives you. You don't need to set up your computer like you would if they were on a network. By configuring your settings to work automatically, you leave the work to be done by your ISP servers. In addition, DHCP does not require authentication, and your IP will stay hidden when you activate the network. You will just need to wait for the DHCP server to give you a random IP from all available Internet IP addresses. To use PPPOE, you will need to authenticate first. Once your account password is verified, you will be assigned a valid IP address. PPPoE is commonly used to allow a large number of hosts to form one network unit that can control and bill each host separately. It's mostly used in areas like communities, buildings, and campuses. The existing ADSL technology has PPPoE protocol integrated into it. Typically, DHCP is used to assign IP addresses dynamically to a company's LAN or Internet. Final words In conclusion, PPPoE and DHCP are both useful protocols for networking. However, some differences between them may make one more suitable for your needs than the other. As always, you can consult us to determine which protocol would be best for your situation.

Published - Sun, 30 Oct 2022

Created by - Orhan Ergun

AWS SAA vs. CLF - Can I skip one?

AWS are known for their famous highly demanded Solutions Architect Associate (SAA) Certificate, and many thinks that it is the first step with AWS and Cloud Computing, the question now is it?, or is there any step that should be taken before, like the AWS Cloud Practitioner CLF exam?. In this blog post we will discover and compare the agenda and the main pillars each exam teach you, and see if it worth skipping CLF and start directly with SAA. Cloud Concepts Your very first chapter to start studying AWS CLF with will be the cloud concepts, this will give a general overview of what is the idea and concept of cloud computing, what would AWS provide regarding that, and are you about to experience. Luckily this part is shared between both the exams of AWS CLF and SAA, and we'll find a share for it here and there, to understand what we are about to start with such exams. that makes them equal here, 1-1. Security and Compliance Having zero knowledge about cloud computing and the restrictions and differentiations that might occur with it, upon implementing a new network on the cloud for the first time will require the knowledge of official documents, government restrictions and compliances, regional compliances as well. Now that is a point where CLF wins as it mentions and provides all the necessary documents and resources to check the security and compliances requirements based on the region you are planning to implement a cloud network on. so far 2-1 for CLF. AWS Core Services This pillar represent the back bone of whatever you should study and learn with AWS, all the services hosted on cloud, in other words, inside AWS real Data Centers, are shown and detailed here, service after another. The CLF exam focuses for more than 30% of its weight on the Core services giving you a good knowledge to call it a start with AWS, while the SAA exam is "about" this pillar, you will spend your time with that exam studying the core services, designing the core services, architecting solutions together, all within the same cloud, one solid well-built/designed network on the cloud of AWS. In general, you will learn about the Core services of AWS 3 times more with SAA compared to CLF, making SAA the ultimate beginning with AWS services. we can say it is a point to SAA, so we have 2-2 now. AWS Economics The last pillar to check and talk about in this post is the one that teaches you billing, payments, discounts, Free tier, support, programs, and pricings. All of that is in the CLF exam but NOT mentioned in the SAA exam unfortunately, it is a major and big point for the CLF as ignoring these skills will result is disasters when dealing with AWS services in real life. And that sent the last point for today to the CLF exam, 3-2. Conclusion With all the above being said, does that make starting with AWS SAA directly a mistake or a wrong step in the path of AWS carrier for me! The Answer is that you can practice and prepare the best with AWS by: Either Start with CLF and then SAA Or, start with SAA but refer to the official documents from AWS the fills the gaps of Compliance and Economics which will be equal to the amount of time and efforts spend studying the CLF exam! Resources For us on orhanergun.net, we provide both the AWS CLF and AWS SAA exams courses on the website, detailed explanation based on the official agenda of the exams by AWS, alongside with many other AWS and Cloud courses, you can either get a life-time subscription per course, which will provide all the future exam updates for free. or contact our sales to get a full annual access to a variety of courses based on the tier you desire.

Published - Wed, 20 Apr 2022

Created by - Orhan Ergun

OSPF Administrative Distance - How preferred is it

OSPF Administrative Distance, or OSPF AD, is the key of electing OSPF among other routing protocols (if existed) leading to the same target within the same routing table, in this blog post we will discover the basics and types of Administrative Distances for OSPF across multiple different platform. Administrative Distance For Cisco systems operating systems, regardless of their platforms, all the IOS-XE, IOS-XR, and NX-OS OS's treats OSPF based on the "AD" which has the value of "110". Now the most important thing is not just to know the numerical value which will be useless without knowing its order of preference among the other routing protocol Administrative Distances. OSPF AD with Cisco OS's The values will be as follows regarding the Static and Dynamic Routing Protocols: Direct = 0 Static = 1 eBGP = 20 EIGRP = 90 OSPF 110 IS-IS = 115 RIP = 120 iBGP = 200 This Shows that OSPF routes to a specific target can be hidden if one of the dynamics (EIGRP or eBGP) routes was installed in the routing table, that also includes the Direct and Static as well. Route Preference Dealing with devices/platforms from Juniper Networks will get you to face and operate with JunOS, the one unified operating system they have, across their different platforms. with juniper the concept of Administrative Distance still exists and still play the same role, but instead, they name it only differently here by calling it as "Route Preference". OSPF AD with Juniper JunOS Some protocols will be treated differently here, and some others will be missing (cases like EIGRP as it is a Cisco proprietary). Direct/Local = 0 Static = 5 OSPF internal = 10 IS-IS L1/L2 = 15/18 RIP = 100 OSPF external = 150 IS-IS external L1/L2 = 160/165 BGP = 170 OSPF here has to types of routes and stands in the middle of the table, with the absence of EIGRP, only Direct/Local and Static routes can beat OSPF routes, making it the most preferred dynamic routing protocol. Routing Protocol Preference With another operating system like Huawei's Versatile Routing Platform (VRP) we will see many similarities with the one of JunOS, but there is a small difference to catch in the table described below. OSPF AD with Huawei's VRP Still missing EIGRP here, check the surprise of where OSPF stands within the table: Direct = 0 OSPF = 10 IS-IS L1/L2 = 15/18 Static = 60 RIP = 100 OSPF external = 150 BGP = 255 OSPF is the first protocol here!, putting away the Static route, even IS-IS beats Static route as well, interesting... Route Preference Again One more platform to check their preferences and that would be The Nokia Service Router Operating System (SR OS). OSPF AD with Nokia's SR OS It has the same name and many similar numbers to Juniper's JunOS table: Direct = 0 Static = 5 OSPF = 10 IS-IS L1/L2 = 15/18 OSPF external 150 IS-IS external L1/L2 = 160/165 BGP = 170 So at the end we find Cisco is almost the only one who names it differently, have different protocols, different order, and clearly different numbers of values for the Administrative Distances.

Published - Wed, 20 Apr 2022

Created by - Orhan Ergun

OSPF Routing Protocol Network Engineer Interview Questions!

OSPF is the most common network engineer interview topics without any doubt. Almost all network engineers faced with some OSPF questions in their interview. Thus I thought it is important to cover common questions and the answer with the blog post.From OSPF LSAs to OSPF Areas, by having Multi Area Hierarchical OSPF for stability, OSPF security and OSPF Fast Convergence, I prepared many questions and explaining them in detail in the below video.   There are many questions in the video and if you liked the video, subscribe to Orhan Ergun YouTube Channel and share your thoughts in the comment section.    Note: OSPF Interview Questions in this video from basics to advanced level and studying this 65 minutes video will enhance your OSPF knowledge definitely!   [embed]https://www.youtube.com/watch?v=2DGhGCGwU3o&t=76s[/embed]

Published - Fri, 07 Aug 2020

Created by - Orhan Ergun

Book Giveaway Winners

As you know couple days ago I announced that I will giveaway 3 of my books to 10 people. In this post, you will see the names of the winners. Thanks for the all participants and I am glad to share my efforts with the community. Also I have many new connections who I can provide useful content by the time. At the end of the post, you will see another surprise by me!         1022 people liked it, some of them was 2nd level connection while they liked, and some of them applied after 11pm gmt+3 on Sunday Feb9, 2020. Thus, 894 people were counted as eligible. Random name picker on https://commentpicker.com/random-name-picker.php was used to pick the names. List of the people who won the books as below. We will be connecting them to learn which book they want to receive from us.   Akinfemi Akinyanju Dennis Krulac Vannaro Mao Navid Yahyapour Vuthha Seang Marius Viotel Nastasa Luca Banfo Ahsan Mateen Abderrahmane Bendaoud Siva Ntshobane Hassan Shah   I would give the books to 10 people but one of my LinkedIn followers wanted to give one book as a gift, thus we selected 11 people. Thanks IGHO, excellent behavior.   During the giveaway campaign, I have seen very helpful people, have a look at below one.     Thanks all those participant. You love reading!  Thus, maybe another help,  I want to give anyone who read this post ' Any of my books till Feb 15,2020 ' will be $25 by using the below links. CCDE In-Depth Service Provider Design and Architecture Segment Routing Theory and Practical Approach       

Published - Mon, 10 Feb 2020

Created by - Orhan Ergun

Recommended Networking Resources for September 2019 Second Week

There are so many good resources for Network Engineers out there. I started to share the ones I liked last week. Click here to see September 2019, First Week Networking Recommended Resources. As you know, I will share 5 resource every week. There are so many in my list already, I can’t wait for the next week to share next recommended 5 resources! Let’s start. This post is explaining the basics of Active-Active Datacenter concept.https://www.missioncriticalmagazine.com/blogs/14-the-mission-critical-blog/post/89161-architecting-for-activeactive-data-centers BGP Information Security is very important to secure Global Internet. Origin Validation can be done in two ways, IRR and RPKI, Networks can have both at the same time. Below post explains RPKI (Resource Public Key Infrastructure) in very good detail.https://blog.cloudflare.com/rpki-details/ BIER (Bit Indexed Explicit Replication) is very cool new tool for scalable IP and MPLS Multicast Design. When I explain it in few words, I say, Segment Routing removes the requirement of LDP and RSVP for Transport LSP in MPLS, BIER does the same thing for Multicast Traffic. You don’t need PIM, mLDP etc.Below Packet Pusher podcast is all about BIER and couple other cool Datacenter specific Routing protocols (RFC 7938 type of Datacenter routing protocol) RIFT and BGP+SFC.PQ Show 115: BIER, RIFT & BGP+SFC At IETF 98 Is IPv6 faster than IPv4? Let’s try to understand what are the considerations IPv4 or IPv6 can be faster. Below APNIC post have some good statistics as well. Why is IPv6 faster? We have Flat Internet concept. Many large ASes exchange traffic in either Private or Public Peering with each other directly. Those networks are directly connected and their traffic is just one hop away. This effectively reduces average AS-Path length to 4 in Global Internet Routing Table (Commonly known as DFZ- Default Free Zone). This research paper is explaining with a great analysis about Flat Internet paradigm and how networks are just one hop away mostly in today Internet.

Published - Fri, 08 Nov 2019

Created by - Orhan Ergun

Recommended Networking Resources for September 2019 Third Week

There are so many good resources for Network Engineers out there. I started to share the ones I liked on beginning of this month. Click here to see previous Networking Recommended Resources. As you know, I share 5 resource every week. There are so many in my list already, I can’t wait for the next week to share next recommended 5 resources! Let’s start. 1. Below video is explaining different NAT concepts, specifically CGN (Carrier Grade NAT) and present some good statistics about usage of CGN in Mobile/Cellular Networks. 2. BGP Information Security is very important to secure Global Internet. BGP Leaks effect potentially millions of users when it happens. Below post explains ‘What is BGP Route Leak’ , starting from ‘What is BGP’ and shows an example how by starting intentional Route Leak to steal crypto currency. https://blog.cloudflare.com/bgp-leaks-and-crypto-currencies/ 3. Nice video on SD-WAN at DKNOG. Explaining some technical details but mainly stay at the architectural level. 4. For those who are looking to understand Diffserv (Differentiated Services) Quality of Service Architecture, must read RFC 4594. https://tools.ietf.org/html/rfc4594 5. Today, most of the IP networks use PIM (Protocol Independent Multicast) when they have Multicast in their networks.Before PIM, DVMRP was deployed in many large scale networks. In the below video, GEANT (European Research Institute) explains how they deployed DVMRP and how they migrated from DVMRP to PIM, and the reasons for migration.

Published - Fri, 08 Nov 2019

Created by - Orhan Ergun

Recommended Networking Resources for September 2019 First Week

I would like to share with you every week some networking resources , can be video , article , book , diagram , another website etc. Whatever I believe can be useful for the computer network engineers, mobile network providers, satellite engineers ,transmission experts, datacenter engineers,  basically whatever I am interested in and I like, I will share in a blog post. There will not be any order of importance among the resources. You can open and go through anyone you want. I will try to limit the list with 5 resources as I want you to read the posts that I publish on the website. Sometimes can be more than 5 though! Let’s get started! TCP vs QUIC – Quic is a new transport protocol I think everyone should have a look at. What are the high level differences between them etc. TCP vs QUIC: A New Transport Protocol 2.  Below post explains how BGP As-Path prepending , when it is done more than couple times , can be dangerous for the attacks on BGP information security Excessive BGP AS-PATH prepending is a self-inflicted vulnerability 3.  This presentation is one of the best presentation about BGP Add-Path, or maybe it is not good to do Add-path. https://ripe60.ripe.net/presentations/Raszuk-To_add-paths_or_not_to_add-paths.pdf 4. In the below video, Randy Bush is talking about IPv6 Transition mechanisms and Operational reality of the different transition mechanisms. 5.  In the below white paper, you can have a look at recent enhancements in MPLS Traffic Engineering. Concept like RSVP- Multipath (TE++) is explained in the paper. http://www.sanog.org/resources/sanog27/SANOG27_Conference_RecentAdvancesInMPLS-TE.pdf If you would like to see more resources weekly, let me know in the comment box below. Whatever is your feedback, let us communicate in the comment section of the blog. Hope this will be useful for you! I love networking, I love helping people who like it!

Published - Fri, 08 Nov 2019