•Availability / Ketersediaan

•Reliability / Kehandalan

•Confidentiality / Kerahasiaan

•Cara Pengamanan Jaringan Komputer:
–Autentikasi
–Enkripsi


Autentikasi
•Proses pengenalan peralatan, sistem operasi, kegiatan, aplikasi dan identitas user yang terhubung dengan jaringan komputer

•Autentikasi dimulai pada saat user login kejaringan dengan cara memasukkan password


Tahapan Autentikasi

1. Autentikasi untuk mengetahui lokasi dari peralatan pada suatu simpul jaringan (data link layer dannetwork layer)
2. Autentikasi untuk mengenal sistemo perasi yang terhubung kejaringan (transport layer)
3. Autentikasi untuk mengetahuifungsi /proses yang sedang terjadi disuatu simpul jaringan (session danpresentation layer)
4. Autentikasi untuk mengenali user dan aplikasi yang digunakan
(application layer)

•Teknik pengkodean data yang berguna untuk menjaga data / file baik didalam komputer maupun pada jalur komunikasi dari pemakai yang tidak dikehendaki

•Enkripsi diperlukan untuk menjaga kerahasiaan data

Segala bentuk ancaman baik fisik maupun logik yang langsung atau tidak langsung mengganggu kegiatan yang sedang berlangsung dalam jaringan.

Faktor-Faktor Penyebab Resiko
Dalam Jaringan Komputer
􀂾Kelemahan manusia (human error)
􀂾Kelemahan perangkat keras komputer
􀂾Kelemahan sistem operasi jaringan
􀂾Kelemahan sistem jaringan komunikasi


•FISIK
-Pencurian perangkat keras komputer atau
perangkat jaringan
-Kerusakan pada komputer dan perangkat
komunikasi jaringan
-Wiretapping
-Bencana alam

•LOGIK
-Kerusakan pada sistem operasi atau aplikasi
-Virus
-Sniffing

•Sniffer
Peralatan yang dapat memonitor proses yang sedang berlangsung

•Spoofing
Penggunaan komputer untuk meniru( dengan cara menimpa identitas atau alamat IP.

•Remote Attack
Segala bentuk serangan terhadap suatu mesin dimana penyerangnya tidak memiliki kendali terhadap mesin tersebut karena dilakukan dari jarak jaruh dluar sistem jaringan atau media transmisi

•Hole
Kondisi dari software atau hardware yang bisa diakses oleh pemakai yang tidak memiliki otoritas atau meningkatnya tingkat pengaksesan tanpa melalui proses otorisasi


•Phreaking
Perilakumenjadikansistempengamananteleponmelemah
•Hacker
–Orangyang secaradiam-diammempelajarisistem
yang biasanyasukardimengertiuntukkemudian
mengelolanyadanmen-share hasilujicobayang
dilakukannya.
–Hacker tidakmerusaksistem
•Craker
–Orangyang secaradiam-diammempelajarisistem
denganmaksudjahat
–Munculkarenasifatdasarmanusiayang selaluingin
membangun(salahsatunyamerusak)
BeberapaBentukAncamanJaringan
•Cracker
–Ciri-ciricracker :
•Bisamembuatprogram C, C++ ataupearl
•MemilikipengetahuanTCP/IP
•Menggunakaninternet lebihdari50 jam per-
bulan
•MenguasaisistemoperasiUNIX atauVMS
•Sukamengoleksisoftware atauhardware lama
•Terhubungkeinternet untukmenjalankan
aksinya
•Melakukanaksinyapadamalamhari, dengan
alasanwaktuyang memungkinkan, jalur
komunikasitidakpadat, tidakmudahdiketahui
oranglain
BeberapaBentukAncamanJaringan
Craker
–Penyebabcracker melakukanpenyerangan:
•spite, kecewa, balas dendam
•sport, petualangan
•profit, mencarikeuntungandariimbalan
oranglain
•stupidity, mencariperhatian
•cruriosity, mencariperhatian
•politics, alasanpolitis
BeberapaBentukAncamanJaringan
Cracker
–Ciri-ciritarget yang dibobolcracker :
•Sulitditentukan
•Biasanyaorganisasibesardanfinancial dengansistem
pengamananyang canggih
•Bilayang diboboljaringankecilbiasanyasistem
pengamanannyalemah, danpemiliknyabarudalambidanginternet
–Ciri-ciritarget yang “berhasil”dibobolcracker :
•Penggunabisamengakses, bisamasukkejaringantanpa
“nama”dan“password”
•Pengganggubisamengakses, merusak, mengubahatau
sejenisnyaterhadapdata
•Pengganggubisamengambilalihkendalisistem
•Sistemhang, gagalbekerja, reboot atausistemberada
dalamkondisitidakdapatdioperasikan
ManajemenResiko
•PengumpulanInformasi
•Analisis
•Output
PengumpulanInformasi
•IdentifikasiAssets
–PerangakatKeras
–PerangkatLunak(SistemOperasidan
Aplikasi)
–PerangkatJaringandanKomunikasi
Data
–PenggunaJaringan
–Lingkungan
–SaranaPendukunglainnya
PengumpulanInformasi
•PenilaianterhadapsegalabentukAncaman(threat)
PengumpulanInformasi
•Penilaianterhadapbagianyang berpotensiterkenagangguan(vulnerability)
•Penilaianterhadapperlindunganyang effektif(safeguard)
–keamananfasilitasfisikjaringan
–keamananperangkatlunak
–keamananpenggunajaringan
–keamanankomunikasidata
–keamananlingkunganjaringan

FORM

[VERB+ed] or irregular verbs

USE 1 Completed Action in the Past

Use the Simple Past to express the idea that an action started and finished at a specific time in the past. Sometimes, the speaker may not actually mention the specific time, but they do have one specific time in mind.

USE 2 A Series of Completed Actions

We use the Simple Past to list a series of completed actions in the past. These actions happen 1st, 2nd, 3rd, 4th, and so on.

USE 3 Duration in Past

The Simple Past can be used with a duration which starts and stops in the past. A duration is a longer action often indicated by expressions such as: for two years, for five minutes, all day, all year, etc.

USE 4 Habits in the Past

The Simple Past can also be used to describe a habit which stopped in the past. It can have the same meaning as "used to." To make it clear that we are talking about a habit, we often add expressions such as: always, often, usually, never, when I was a child, when I was younger, etc.

USE 5 Past Facts or Generalizations

The Simple Past can also be used to describe past facts or generalizations which are no longer true. As in USE 4 above, this use of the Simple Past is quite similar to the expression "used to."

IMPORTANT When-Clauses Happen First

Clauses are groups of words which have meaning but are often not complete sentences. Some clauses begin with the word "when" such as "when I dropped my pen..." or "when class began..." These clauses are called when-clauses, and they are very important. The examples below contain when-clauses.

When-clauses are important because they always happen first when both clauses are in the Simple Past. Both of the examples above mean the same thing: first, I paid her one dollar, and then, she answered my question. It is not important whether "when I paid her one dollar" is at the beginning of the sentence or at the end of the sentence. However, the example below has a different meaning. First, she answered my question, and then, I paid her one dollar.

ADVERB PLACEMENT

The examples below show the placement for grammar adverbs such as: always, only, never, ever, still, just, etc.

ACTIVE / PASSIVE

The simple past expresses an action in the past taking place once, never, several times. It can also be used for actions taking place one after another or in the middle of another action.

Form of Simple Past

	Positive	Negative	Question
no differences	I spoke.	I did not speak.	Did I speak?

For irregular verbs, use the past form. For regular verbs, just add “ed”.

Exceptions in Spelling when Adding ‘ed’

Exceptions in spelling when adding ed	Example
after a final e only add d	love – loved
final consonant after a short, stressed vowel or l as final consonant after a vowel is doubled	admit – admitted travel – travelled
final y after a consonant becomes i	hurry – hurried

Use of Simple Past

• action in the past taking place once, never or several times

  Example: He visited his parents every weekend.

• actions in the past taking place one after the other

  Example: He came in, took off his coat and sat down.

• action in the past taking place in the middle of another action

  Example: When I was having breakfast, the phone suddenly rang.

• if sentences type II (If I talked, …)

  Example: If I had a lot of money, I would share it with you.

Simple Past Tense digunakan untuk menyatakan kalimat yang sudah berlalu

Rumus Simple Past Tense

S + was,were + adjective / S + V2 + Object

Example : I was happy yesterday, I went to school with my father this morning

Negative : You were not happy yesterday, I didn't go to school with my father

Interogative : Were you happy yesterday ? , Did you go to school ?

The simple past tense is used to talk about actions that happened at a specific time in the past. You state when it happened using a time adverb.

You form the simple past of a verb by adding -ed onto the end of a regular verb but, irregular verb forms have to be learned.

To be Statements +	To be Statements -	Questions ?
I was.	I wasn't.	Was I?
He was.	He wasn't.	Was he?
She was.	She wasn't.	Was she?
It was.	It wasn't.	Was it?
You were.	You weren't.	Were you?
We were.	We weren't.	Were we?
They were.	They weren't.	Were they?

Regular Verb (to work) Statements +	Regular Verb (to work) Statements -	Questions	Short answer +	Short answer -
I worked.	I didn't work.	Did I work?	Yes, I did.	No, I didn't.
He worked.	He didn't work.	Did he work?	Yes, he did.	No, he didn't.
She worked.	She didn't work.	Did she work?	Yes, she did.	No, she didn't.
It worked.	It didn't work.	Did it work?	Yes, it did.	No, it didn't.
You worked.	You didn't work.	Did you work?	Yes you did.	No, you didn't.
We worked.	We didn't work.	Did we work?	Yes we did.	No, we didn't.
They worked.	They didn't work.	Did they work?	Yes they did.	No, they didn't.

Simple Past Timeline

For example:

"Last year I took my exams."

"I got married in 1992."

It can be used to describe events that happened over a period of time in the past but not now.

For example:

"I lived in South Africa for two years."

The simple past tense is also used to talk about habitual or repeated actions that took place in the past.

For example:

"When I was a child we always went to the seaside on bank holidays."

Take a look at the following conjugation chart. Notice from the above dialogue and following chart that the present continuous (progressive) is used to describe what is happening at the moment. It is also used to describe a plan in the near future (this evening, next week, on Saturday, etc.). The present continuous (progressive) is often used with: now, at the moment, today, this morning - afternoon - evening.

IMPORTANT NOTES:

• The present continuous (progressive) is used only with action verbs. Example: I am working at the moment NOT I am believing you.
• The present continuous (progressive) is also used to describe an action which is happening around this moment: Example: I'm reading 'Just in Time' this week. I'm not reading the book at this particular moment, but around this time.

Examples	Usage
What are you cooking? Tom is studying for his exams at the moment. It isn't raining now. We can go outside.	Actions happening at the present moment.
What are you doing this weekend? I'm meeting Peter tomorrow morning. We're driving to Albany this weekend.	Planned future events (usually in the near future)
We're currently working on the Smith account. What classes are you taking this semester? We're studying Greek history this month.	Actions or events happening around the present moment.

Structure

In the positive form, follow the form S To be Verb -ing. Remember that you need to conjugate the auxiliary verb 'to be'. I am (I'm) You are (You're) He, She, It is (He's, She's, It's) We, You, They are (We're, You're, They're) eating lunch at noon.

Conjugate the helping verb 'To Be' Not Verb - ing to form negatives. I am not (I'm not) You are not (You aren't) He, She, It is not (He, She, It isn't We, You, They are not (We, You, They aren't) coming this evening.

Conjugate the helping verb 'To Be' S Verb - ing in question forms. Are you we they listening to me? Is he she it listening to me?

The present progressive is formed by combining the verb "to be" with the present participle. (The present participle is merely the "-ing" form of a verb.)

I am studying.
I am studying with María.

In English, present progressive can be used to describe what is happening now, or what will happen in the future.

I am studying now.
I am studying with María tonight.

In Spanish, the present progressive is only used to describe an action that is in the process of taking place. It is not used for future actions.

I am studying now.
(use present progressive)

I am studying with María tonight.
(do not use present progressive)

To form the present progressive in Spanish, combine a form of "estar" with the present participle.

Estoy hablando.
I am speaking.

Juan está comiendo.
John is eating.

María está escribiendo una carta.
Mary is writing a letter.

In order to form the present progressive, you must know how to conjugate the verb estar, and how to form the present participle. You already know how to conjugate the verb estar:

estar

estoy
estás
está
estamos
estáis
están

To form the present participle of regular -ar verbs, add -ando to the stem of the verb.

hablar: hablando
(hablar - ar + ando)

trabajar: trabajando
(trabajar - ar + ando)

estudiar: estudiando
(estudiar - ar + ando)

To form the present participle of regular -er and -ir verbs, add -iendo to the stem of the verb.

comer: comiendo
(comer - er + iendo)

hacer: haciendo
(hacer - er + iendo)

vivir: viviendo
(vivir - ir + iendo)

escribir: escribiendo
(escribir - ir + iendo)

To form the present participle of -ir stem changing verbs, change e:i and o:u in the stem, and then add -iendo to the stem of the verb.

servir: sirviendo
pedir: pidiendo
decir: diciendo

dormir: durmiendo
morir: muriendo
poder: pudiendo

Sometimes when forming the present participle it is necessary to change the spelling of a word so that it agrees with the way it is pronounced. We call this an "orthographic" change. Here are some common examples:

caer: cayendo
creer: creyendo
huir: huyendo
ir: yendo
influir: influyendo
oír: oyendo
traer: trayendo
leer: leyendo
seguir: siguiendo

The following examples illustrate the rules for forming the present participle.

hablar: hablando (-ar)
comer: comiendo (-er)
vivir: viviendo (-ir)
decir: diciendo (e:i)
dormir: durmiendo (o:u)
leer: leyendo (orthographic)
seguir: siguiendo (orthographic)

To form the present progressive, simply conjugate the verb estar to agree with the subject of the sentence, and follow it with the present participle.

Juan está comiendo pan.
John is eating bread.

María y Carmen están hablando con nosotros.
Mary and Carmen are speaking with us.

Remember, only use the present progressive for actions that are "in progress." Compare the uses of the present indicative with the uses of the present progressive.

Estudio español. (Present Indicative)

I study Spanish.
I am studying Spanish (these days).
I do study Spanish.

Estoy estudiando español. (Present Progressive)

I am studying (right now, at this moment) Spanish.

It is important to remember that you would never use the present progressive to say something like "We are going to Spain this summer." Use present progressive only for actions that are "in progress."

Let's add two more verb flashcards: one for present progressive and one for practice in forming the present participle:

Verb Flashcards
Complete List

Present Progressive

estar + present participle
I am speaking (right now, at this moment)
Never use present progressive for something that will occur in the future.

Present Participle (-ando, -iendo, yendo)

hablar - hablando (-ar)
comer - comiendo (-er)
vivir - viviendo (-ir)
decir - diciendo (e:i)
dormir - durmiendo (o:u)
leer - leyendo (orthographic)
seguir: siguiendo (orthographic)