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<metadesc>How to crack GATE exam in Computer Science and Engineering</metadesc> | <metadesc>How to crack GATE exam in Computer Science and Engineering</metadesc> | ||
− | First of all don't tell u want to crack GATE. Cracking GATE is very difficult- there are more than 200,000 people trying to do it and only about 2000 seats including NITs. But if you study your bachelor subjects in the right way, GATE will automatically come to you. No extra preparation is needed. Take a look at GATE [http:// | + | First of all don't tell u want to crack GATE. Cracking GATE is very difficult- there are more than 200,000 people trying to do it and only about 2000 seats including NITs. But if you study your bachelor subjects in the right way, GATE will automatically come to you. No extra preparation is needed. Take a look at GATE [http://syllabus.gatecse.in syllabus], note down the important ones, and note down the important topics in them. For those subjects, use Standard text books, understand the topics well by doing practice problems at the end of the chapters (like doing exercises in Cormen). You live in Google era, every topic is just a click away. So, there's no excuse for saying teachers in college are bad. With one click you can get MIT lectures or NPTEL lectures. For doubt clearance, there are stack overflow, fb groups etc.. So, everything is there for you. Those who use them will be far ahead of others. So, all the best for you. I hope you wouldn't need to crack GATE at the end of 4 years. Wish you'll just walk through it :) |
− | Most of the classes in Engineering colleges might be below standard. But now you can learn from the best lectures around the world. Subscribe to the | + | Most of the classes in Engineering colleges might be below standard. But now you can learn from the best lectures around the world. Subscribe to these [[Video Lectures|Courses]] given by the best in the world and get the real knowledge. |
− | [ | + | [https://www.facebook.com/notes/gate-computer-science/great-tips-by-previous-gate-topper-from-iit-b/404542332911359 Great tips from a GATE topper] |
+ | |||
+ | ==Important Topics for GATE== | ||
+ | <html><h3> | ||
+ | <p class="P14">C & DS </p></h3><p class="Standard"> </p><p class="Standard"><b>Important Points :</b></p><p class="Standard"> </p><p class="Standard">This is the most important subject according to GATE point of you. Approximately 25% Questions in Gate come from above topics and all are related with each other. If you are good in this subject this will not only help you in GATE but also after it in so many written exams and interviews of Different IITs and IIITs.</p><p class="Standard"> </p><p class="Standard"> </p><p class="Standard">C programming Questions are mostly based on finding outputs which contain some pointers, static variables, arrays, strings, functions etc. So the best way to practice C programming question is take questions from different books, try to solve them and try to do programming on Compiler. It will increase your skills and accuracy. Very high chances of common data questions. So if you are not good at programming start practice from now.</p><p class="Standard"> </p><p class="Standard"> </p><p class="Standard">Understand Different Problems on Stack, Queue, Link List. Generally they come in a C program, But you can solve them only if you know the logic. Properties of Heap. Deletion and insertion of items in the heap.</p><p class="Standard"> </p><p class="Standard"> </p><p class="Standard">Practice Tree problems like no of leaf nodes, non leaf nodes, total nodes, height of the tree, no of full nodes, mirror image, etc. AVL tree and balancing them on insertion and Deletion. Binary tree, Binary Search Tree, Inorder, Preorder, Postorder traversal. Spanning Trees, Minimum Spanning Tree problems.</p><p class="Standard"> </p><p class="Standard"> </p><p class="Standard">Finding Complexity : Very Important Topic. You need to practice more and with every problem you solved. Sometimes direct question comes related to complexity like give complexity of Heap sort. But mostly you are given a code or question. You need to find best average case complexity of that problem. So try to find complexity of every algorithm or program which you practice. Also understand properties of complexity. Sometimes relation between them is asked.</p><p class="Standard"> </p><p class="Standard">Searching and Sorting Problems. Difference between Different Techniques and how to apply them on different real life problems.</p><p class="Standard"> </p><p class="Standard">Questions on approach of dynamic programming, Divide and Conquer, Greedy and Brute Force. Practice basic problems like quick sort, merge sort, knapsack problem, matrix chain multiplication, LCS, Job sequencing, Compressing Mechanism. It will help you to solve other tricky problems.</p><p class="Standard"> </p><p class="Standard"> </p><p class="Standard">Basic Theory of P-NP class</p><h3 class="P19"><a id="a__Operating_System "><span/></a>Operating System </h3><p class="P4"> </p><p class="P2"><span class="T5">Syllabus</span><span class="apple-converted-space"><span class="T5"> </span></span><span class="T2">: Processes, Threads, Inter-process communication, Concurrency, Synchronization, Deadlock, CPU scheduling, Memory management and virtual memory, File systems, I/O systems, Protection and security.</span></p><p class="P4"> </p><h4 class="P16"><a id="a__Important_Points__"><span/></a>Important Points :</h4><ul><li><p class="P5" style="margin-left:0cm;"><span class="WW8Num3z0" style="display:block;float:left;min-width:0.635cm;"></span>Scheduling : Numerical Questions have more chances. Practice more in finding turn around time and waiting time of different scheduling policies.<span class="odfLiEnd"/> </p></li><li><p class="P5" style="margin-left:0cm;"><span class="WW8Num3z0" style="display:block;float:left;min-width:0.635cm;"></span>Deadlock : Bankers Algo, Given Sequence is safe or not. Chances of common data or linked questions.<span class="odfLiEnd"/> </p></li><li><p class="P5" style="margin-left:0cm;"><span class="WW8Num3z0" style="display:block;float:left;min-width:0.635cm;"></span>Synchronization : High Probability Of Questions in exam. Practice some question related to semaphores and classical problems of synchronization (this will help you to solve other questions)<span class="odfLiEnd"/> </p></li><li><p class="P5" style="margin-left:0cm;"><span class="WW8Num3z0" style="display:block;float:left;min-width:0.635cm;"></span>Memory Management : Questions generally comes from page table size, number of pages, logical address, physical address, page size, inverted page table, virtual memory, TLB etc.<span class="odfLiEnd"/> </p></li></ul><p class="Standard"> </p><p class="Standard"> </p><p class="Standard"> </p><h3 class="P19"><a id="a__Theory_Of_Computation__"><span/></a>Theory Of Computation :</h3><p class="P2"><span class="T5">Syllabus </span><span class="T2">: Regular languages and finite automata, Context free languages and Push-down automata, Recursively enumerable sets and Turing machines, Undecidability.</span></p><p class="P4"> </p><h4 class="P17"><a id="a__Important_Points__"><span/></a>Important Points :</h4><ul><li><p class="P6" style="margin-left:0cm;"><span class="WW8Num9z0" style="display:block;float:left;min-width:0.635cm;"></span>Finite Automata covers approximately 50% questions from TOC. So give it more time then others. Do questions realted to finding minimum number of states, NFA to DFA conversion, Closure Properties of finite automata, Finding Regular Expressions,mealy moore machine etc.<span class="odfLiEnd"/> </p></li><li><p class="P6" style="margin-left:0cm;"><span class="WW8Num9z0" style="display:block;float:left;min-width:0.635cm;"></span>In Context free grammer practice more on simplification of CFG, pushdown automata, closure properties etc.<span class="odfLiEnd"/> </p></li><li><p class="P6" style="margin-left:0cm;"><span class="WW8Num9z0" style="display:block;float:left;min-width:0.635cm;"></span>Do problems on finding category of any language or grammar.<span class="odfLiEnd"/> </p></li><li><p class="P6" style="margin-left:0cm;"><span class="WW8Num9z0" style="display:block;float:left;min-width:0.635cm;"></span>Concepts related to expressive power of different languages.<span class="odfLiEnd"/> </p></li><li><p class="P6" style="margin-left:0cm;"><span class="WW8Num9z0" style="display:block;float:left;min-width:0.635cm;"></span>Basic problems related to NP-Completeness. Properties of Recursive and Recursive Enumerable Languages.<span class="odfLiEnd"/> </p></li><li><p class="P6" style="margin-left:0cm;"><span class="WW8Num9z0" style="display:block;float:left;min-width:0.635cm;"></span>Turing Machine making and expressive power of different type of turing machine. ( also useful for interview )<span class="odfLiEnd"/> </p></li></ul><p class="Standard"> </p><p class="Standard"> </p><p class="Standard"> </p><p class="Standard"> </p><p class="Standard"> </p><p class="Standard"> </p><p class="Standard"> </p><h3 class="P20"><a id="a__Compiler_Design"><span/></a>Compiler Design</h3><p class="P1"><br/></p><h4 class="P16"><a id="a__Important_Points__"><span/></a>Important Points :</h4><ul><li><p class="P7" style="margin-left:0cm;"><span class="WW8Num5z0" style="display:block;float:left;min-width:0.635cm;"></span>Parsing : there is always a question related to parsing. You need to practice all parsing technique because there is also chances for linked questions. finding first and follow, LL(1)-LR(1)-SLR-LALR-CLR.<span class="odfLiEnd"/> </p></li><li><p class="P7" style="margin-left:0cm;"><span class="WW8Num5z0" style="display:block;float:left;min-width:0.635cm;"></span>Precedence and Associativity of operators.<span class="odfLiEnd"/> </p></li><li><p class="P7" style="margin-left:0cm;"><span class="WW8Num5z0" style="display:block;float:left;min-width:0.635cm;"></span>Finding value from expression tree.<span class="odfLiEnd"/> </p></li><li><p class="P7" style="margin-left:0cm;"><span class="WW8Num5z0" style="display:block;float:left;min-width:0.635cm;"></span>Ambiguous grammar.<span class="odfLiEnd"/> </p></li></ul><p class="Standard"> </p><p class="Standard"> </p><h3 class="P18"><a id="a__Databases"><span/></a>Databases</h3><h4 class="P15"><a id="a__Important_Points__"><span/></a>Important Points :</h4><ul><li><p class="P8" style="margin-left:0cm;"><span class="WW8Num10z0" style="display:block;float:left;min-width:0.635cm;"></span>No gate paper completed without Normalization. This is very easy once you understand and can solve questions quickly. Questions are like Finding normal form ( comes 70% times in gate paper ), finding candidate keys, decomposition of relation, loss less join and dependency preservation have more probability to come.<span class="odfLiEnd"/> </p></li><li><p class="P8" style="margin-left:0cm;"><span class="WW8Num10z0" style="display:block;float:left;min-width:0.635cm;"></span>SQL Queries also asked in the paper. Practice select clause properly with properties of having,group by, any ,all, exits. Question may come with relational algebra in common data section.<span class="odfLiEnd"/> </p></li><li><p class="P8" style="margin-left:0cm;"><span class="WW8Num10z0" style="display:block;float:left;min-width:0.635cm;"></span>Practice joins because there is more probability of tricky questions from them.<span class="odfLiEnd"/> </p></li><li><p class="P8" style="margin-left:0cm;"><span class="WW8Num10z0" style="display:block;float:left;min-width:0.635cm;"></span>Finding View and Conflict serializability. Finding Recoverable and Cascade schedule.lock based, Two phase, time stamp and graph based protocal with there properties like deadlock freedom, starvation freedom.<span class="odfLiEnd"/> </p></li><li><p class="P8" style="margin-left:0cm;"><span class="WW8Num10z0" style="display:block;float:left;min-width:0.635cm;"></span>formation and structure of B and B+ tress. primary and clustering index. Numerical Questions from no of block required in indexing of different type, collision resolution, minimum and maximum no of nodes in B,B+ trees.<span class="odfLiEnd"/> </p></li></ul><p class="Standard"> </p><p class="Standard"> </p><h3 class="P20"><a id="a__Digital_Logic"><span/></a>Digital Logic</h3><p class="P2"><span class="T6">Syllabus</span><span class="apple-converted-space"><span class="T6"> </span></span><span class="T4">: Logic functions, Minimization, Design and synthesis of combinational and sequential circuits; Number representation and computer arithmetic (fixed and floating point).</span></p><p class="P4"> </p><h4 class="P17"><a id="a__Important_Points__"><span/></a>Important Points :</h4><ul><li><p class="P9" style="margin-left:0cm;"><span class="WW8Num2z0" style="display:block;float:left;min-width:0.635cm;"></span>Digital logic contains very simple questions. If you practice and use your brain in a right way you can do them easily. <span class="odfLiEnd"/> </p></li><li><p class="P9" style="margin-left:0cm;"><span class="WW8Num2z0" style="display:block;float:left;min-width:0.635cm;"></span>Practice K-Map. very high chances of very simple question. Don't loose your marks here.<span class="odfLiEnd"/> </p></li><li><p class="P9" style="margin-left:0cm;"><span class="WW8Num2z0" style="display:block;float:left;min-width:0.635cm;"></span>Practice Multiplexer, De-multiplexer, Encoder, Decoder questions.<span class="odfLiEnd"/> </p></li><li><p class="P9" style="margin-left:0cm;"><span class="WW8Num2z0" style="display:block;float:left;min-width:0.635cm;"></span>Understand concept of flip flop. They are given and modulas of counter is asked. <span class="odfLiEnd"/> </p></li><li><p class="P9" style="margin-left:0cm;"><span class="WW8Num2z0" style="display:block;float:left;min-width:0.635cm;"></span>Practice questions related to Floating Point representation, integer representation, ieee format, range and precision. <span class="odfLiEnd"/> </p></li></ul><p class="Standard"/><h3 class="P20"><a id="a__Computer_Organization_and_Architecture "><span/></a>Computer Organization and Architecture </h3><p class="P3"><span class="T6">Syllabus :</span><span class="T4"> Machine instructions and addressing modes, ALU and data-path, CPU control design, Memory interface, I/O interface (Interrupt and DMA mode), Instruction pipelining, Cache and main memory, Secondary storage.</span></p><h4 class="P17"><a id="a__Important_Points__"><span/></a>Important Points :</h4><ul><li><p class="P10" style="margin-left:0cm;"><span class="WW8Num8z0" style="display:block;float:left;min-width:0.635cm;"></span>Addressing Modes : Theory and questions <span class="odfLiEnd"/> </p></li><li><p class="P10" style="margin-left:0cm;"><span class="WW8Num8z0" style="display:block;float:left;min-width:0.635cm;"></span>Numerical related to program counter after some instruction, no of one address-two address instructions, Values after shift and rotate instructions, horizontal and vertical programming related questions. <span class="odfLiEnd"/> </p></li><li><p class="P10" style="margin-left:0cm;"><span class="WW8Num8z0" style="display:block;float:left;min-width:0.635cm;"></span>Numerical Problems on Speed up of pipeline, time taken to complete instruction in pipeline and non-pipeline architectures, Hazards in pipeline, hazards removal, branch penalty etc.<span class="odfLiEnd"/> </p></li><li><p class="P10" style="margin-left:0cm;"><span class="WW8Num8z0" style="display:block;float:left;min-width:0.635cm;"></span>Numerical Problems on cache memory organization, mapping technique, multilevel caches, write through and write back technique<span class="odfLiEnd"/> </p></li><li><p class="P10" style="margin-left:0cm;"><span class="WW8Num8z0" style="display:block;float:left;min-width:0.635cm;"></span>Questions are more tricky in this subject. So you need to practice more on different types of Numerical Questions.<span class="odfLiEnd"/> </p></li></ul><p class="Standard"> </p><p class="Standard"> </p><h3 class="P20"><a id="a__Computer_Network"><span/></a>Computer Network</h3><p class="P13"><span class="T5">Syllabus : </span><span class="T2"> ISO/OSI stack, LAN technologies (Ethernet, Token ring), Flow and error control techniques, Routing algorithms, Congestion control, TCP/UDP and sockets, IP(v4), Application layer protocols (icmp, dns, smtp, pop, ftp, http); Basic concepts of hubs, switches, gateways, and routers. Network security – basic concepts of public key and private key cryptography, digital signature, firewalls.</span></p><h4 class="P17"><a id="a__Important_Points__"><span/></a>Important Points :</h4><ul><li><p class="P11" style="margin-left:0cm;"><span class="WW8Num4z0" style="display:block;float:left;min-width:0.635cm;"></span>Addressing related questions : Subnet address, supernet address, brodcast address, range of network, no of host, classless addressing, non continuous addresses, first host and last host finding etc.<span class="odfLiEnd"/> </p></li><li><p class="P11" style="margin-left:0cm;"><span class="WW8Num4z0" style="display:block;float:left;min-width:0.635cm;"></span>Properties Of Circuit Switching and packet switching, Routing Protocols and Numerical Problems on them.<span class="odfLiEnd"/> </p></li><li><p class="P11" style="margin-left:0cm;"><span class="WW8Num4z0" style="display:block;float:left;min-width:0.635cm;"></span>Flow Control and Error Control Policies. Numerical Problems on Window Size, No Of Sequence bits, frame size, bandwidth, round trip time, utilization, Hamming Distance, CRC. Congestion Control policies like slow start, congestion avoidence and Congestion Detection.<span class="odfLiEnd"/> </p></li><li><p class="P11" style="margin-left:0cm;"><span class="WW8Num4z0" style="display:block;float:left;min-width:0.635cm;"></span>IP Header , TCP and UDP header format, theory related to Ethernet and token ring.<span class="odfLiEnd"/> </p></li><li><p class="P11" style="margin-left:0cm;"><span class="WW8Num4z0" style="display:block;float:left;min-width:0.635cm;"></span>Basics Of Different Type of protocols like : FTP, HTTP, DHCP, ARP, RARP, SMTP, ICMP,POP<span class="odfLiEnd"/> </p></li><li><p class="P11" style="margin-left:0cm;"><span class="WW8Num4z0" style="display:block;float:left;min-width:0.635cm;"></span>Basic Concepts of Cryptography and firewalls.<span class="odfLiEnd"/> </p></li></ul><p class="Standard"> </p><p class="Standard"> </p><p class="Standard"> </p><p class="Standard"> </p><p class="Standard"> </p><p class="Standard"> </p><p class="Standard"> </p> </html> | ||
First of all don't tell u want to crack GATE. Cracking GATE is very difficult- there are more than 200,000 people trying to do it and only about 2000 seats including NITs. But if you study your bachelor subjects in the right way, GATE will automatically come to you. No extra preparation is needed. Take a look at GATE syllabus, note down the important ones, and note down the important topics in them. For those subjects, use Standard text books, understand the topics well by doing practice problems at the end of the chapters (like doing exercises in Cormen). You live in Google era, every topic is just a click away. So, there's no excuse for saying teachers in college are bad. With one click you can get MIT lectures or NPTEL lectures. For doubt clearance, there are stack overflow, fb groups etc.. So, everything is there for you. Those who use them will be far ahead of others. So, all the best for you. I hope you wouldn't need to crack GATE at the end of 4 years. Wish you'll just walk through it :)
Most of the classes in Engineering colleges might be below standard. But now you can learn from the best lectures around the world. Subscribe to these Courses given by the best in the world and get the real knowledge.
C & DS
Important Points :
This is the most important subject according to GATE point of you. Approximately 25% Questions in Gate come from above topics and all are related with each other. If you are good in this subject this will not only help you in GATE but also after it in so many written exams and interviews of Different IITs and IIITs.
C programming Questions are mostly based on finding outputs which contain some pointers, static variables, arrays, strings, functions etc. So the best way to practice C programming question is take questions from different books, try to solve them and try to do programming on Compiler. It will increase your skills and accuracy. Very high chances of common data questions. So if you are not good at programming start practice from now.
Understand Different Problems on Stack, Queue, Link List. Generally they come in a C program, But you can solve them only if you know the logic. Properties of Heap. Deletion and insertion of items in the heap.
Practice Tree problems like no of leaf nodes, non leaf nodes, total nodes, height of the tree, no of full nodes, mirror image, etc. AVL tree and balancing them on insertion and Deletion. Binary tree, Binary Search Tree, Inorder, Preorder, Postorder traversal. Spanning Trees, Minimum Spanning Tree problems.
Finding Complexity : Very Important Topic. You need to practice more and with every problem you solved. Sometimes direct question comes related to complexity like give complexity of Heap sort. But mostly you are given a code or question. You need to find best average case complexity of that problem. So try to find complexity of every algorithm or program which you practice. Also understand properties of complexity. Sometimes relation between them is asked.
Searching and Sorting Problems. Difference between Different Techniques and how to apply them on different real life problems.
Questions on approach of dynamic programming, Divide and Conquer, Greedy and Brute Force. Practice basic problems like quick sort, merge sort, knapsack problem, matrix chain multiplication, LCS, Job sequencing, Compressing Mechanism. It will help you to solve other tricky problems.
Basic Theory of P-NP class
Syllabus : Processes, Threads, Inter-process communication, Concurrency, Synchronization, Deadlock, CPU scheduling, Memory management and virtual memory, File systems, I/O systems, Protection and security.
Scheduling : Numerical Questions have more chances. Practice more in finding turn around time and waiting time of different scheduling policies.
Deadlock : Bankers Algo, Given Sequence is safe or not. Chances of common data or linked questions.
Synchronization : High Probability Of Questions in exam. Practice some question related to semaphores and classical problems of synchronization (this will help you to solve other questions)
Memory Management : Questions generally comes from page table size, number of pages, logical address, physical address, page size, inverted page table, virtual memory, TLB etc.
Syllabus : Regular languages and finite automata, Context free languages and Push-down automata, Recursively enumerable sets and Turing machines, Undecidability.
Finite Automata covers approximately 50% questions from TOC. So give it more time then others. Do questions realted to finding minimum number of states, NFA to DFA conversion, Closure Properties of finite automata, Finding Regular Expressions,mealy moore machine etc.
In Context free grammer practice more on simplification of CFG, pushdown automata, closure properties etc.
Do problems on finding category of any language or grammar.
Concepts related to expressive power of different languages.
Basic problems related to NP-Completeness. Properties of Recursive and Recursive Enumerable Languages.
Turing Machine making and expressive power of different type of turing machine. ( also useful for interview )
Parsing : there is always a question related to parsing. You need to practice all parsing technique because there is also chances for linked questions. finding first and follow, LL(1)-LR(1)-SLR-LALR-CLR.
Precedence and Associativity of operators.
Finding value from expression tree.
Ambiguous grammar.
No gate paper completed without Normalization. This is very easy once you understand and can solve questions quickly. Questions are like Finding normal form ( comes 70% times in gate paper ), finding candidate keys, decomposition of relation, loss less join and dependency preservation have more probability to come.
SQL Queries also asked in the paper. Practice select clause properly with properties of having,group by, any ,all, exits. Question may come with relational algebra in common data section.
Practice joins because there is more probability of tricky questions from them.
Finding View and Conflict serializability. Finding Recoverable and Cascade schedule.lock based, Two phase, time stamp and graph based protocal with there properties like deadlock freedom, starvation freedom.
formation and structure of B and B+ tress. primary and clustering index. Numerical Questions from no of block required in indexing of different type, collision resolution, minimum and maximum no of nodes in B,B+ trees.
Syllabus : Logic functions, Minimization, Design and synthesis of combinational and sequential circuits; Number representation and computer arithmetic (fixed and floating point).
Digital logic contains very simple questions. If you practice and use your brain in a right way you can do them easily.
Practice K-Map. very high chances of very simple question. Don't loose your marks here.
Practice Multiplexer, De-multiplexer, Encoder, Decoder questions.
Understand concept of flip flop. They are given and modulas of counter is asked.
Practice questions related to Floating Point representation, integer representation, ieee format, range and precision.
Syllabus : Machine instructions and addressing modes, ALU and data-path, CPU control design, Memory interface, I/O interface (Interrupt and DMA mode), Instruction pipelining, Cache and main memory, Secondary storage.
Addressing Modes : Theory and questions
Numerical related to program counter after some instruction, no of one address-two address instructions, Values after shift and rotate instructions, horizontal and vertical programming related questions.
Numerical Problems on Speed up of pipeline, time taken to complete instruction in pipeline and non-pipeline architectures, Hazards in pipeline, hazards removal, branch penalty etc.
Numerical Problems on cache memory organization, mapping technique, multilevel caches, write through and write back technique
Questions are more tricky in this subject. So you need to practice more on different types of Numerical Questions.
Syllabus : ISO/OSI stack, LAN technologies (Ethernet, Token ring), Flow and error control techniques, Routing algorithms, Congestion control, TCP/UDP and sockets, IP(v4), Application layer protocols (icmp, dns, smtp, pop, ftp, http); Basic concepts of hubs, switches, gateways, and routers. Network security – basic concepts of public key and private key cryptography, digital signature, firewalls.
Addressing related questions : Subnet address, supernet address, brodcast address, range of network, no of host, classless addressing, non continuous addresses, first host and last host finding etc.
Properties Of Circuit Switching and packet switching, Routing Protocols and Numerical Problems on them.
Flow Control and Error Control Policies. Numerical Problems on Window Size, No Of Sequence bits, frame size, bandwidth, round trip time, utilization, Hamming Distance, CRC. Congestion Control policies like slow start, congestion avoidence and Congestion Detection.
IP Header , TCP and UDP header format, theory related to Ethernet and token ring.
Basics Of Different Type of protocols like : FTP, HTTP, DHCP, ARP, RARP, SMTP, ICMP,POP
Basic Concepts of Cryptography and firewalls.
First of all don't tell u want to crack GATE. Cracking GATE is very difficult- there are more than 200,000 people trying to do it and only about 2000 seats including NITs. But if you study your bachelor subjects in the right way, GATE will automatically come to you. No extra preparation is needed. Take a look at GATE syllabus, note down the important ones, and note down the important topics in them. For those subjects, use Standard text books, understand the topics well by doing practice problems at the end of the chapters (like doing exercises in Cormen). You live in Google era, every topic is just a click away. So, there's no excuse for saying teachers in college are bad. With one click you can get MIT lectures or NPTEL lectures. For doubt clearance, there are stack overflow, fb groups etc.. So, everything is there for you. Those who use them will be far ahead of others. So, all the best for you. I hope you wouldn't need to crack GATE at the end of 4 years. Wish you'll just walk through it :)
Most of the classes in Engineering colleges might be below standard. But now you can learn from the best lectures around the world. Subscribe to the courses here and do them with at most effort.