المصادقة الثنائية مهمة بغض النظر عن الجهاز.

In present-tense Arabic, sentences like this often do not use a verb for to be.

So:

• المصادقة الثنائية مهمة
• literally: two-factor authentication important
• naturally: Two-factor authentication is important

This is called a nominal sentence. If you wanted was or will be, then Arabic would usually use a verb such as كان.

Because Arabic adjectives normally come after the noun they describe.

So here:

• المصادقة = authentication
• الثنائية = two-factor / two-step / dual

Together, المصادقة الثنائية means two-factor authentication.

Arabic adjectives also agree with the noun in:

• gender
• number
• definiteness
• case

That is why both words have الـ here:

• المصادقة
• الثنائية

They are both definite.

Because المصادقة is a feminine noun.

You can often recognize feminine nouns by the ending ـة, and مصادقة has that ending.

So anything describing it must also be feminine:

• الثنائية matches المصادقة
• مهمة also matches المصادقة

So the pattern is:

• المصادقة = feminine noun
• الثنائية = feminine adjective
• مهمة = feminine predicate adjective

If the noun were masculine, these forms would usually change.

No. Here الثنائية does not mean the grammatical dual form.

It is an adjective meaning something like:

• twofold
• binary
• dual
• in tech context, two-factor or two-step

So المصادقة الثنائية is a fixed modern term for two-factor authentication.

A learner might see ثنائي and think of two in a grammar sense, but here it is just part of the technical expression.

بغض النظر عن is a very common expression meaning:

• regardless of
• irrespective of
• without considering

So:

• بغض النظر عن الجهاز = regardless of the device

Grammatically, it is a set phrase:

• بـ = with / by
• غضّ النظر = ignoring / overlooking
• عن = about / concerning

You do not need to translate it word by word every time. It is best learned as one chunk:

• بغض النظر عن = regardless of

Arabic often uses a singular definite noun to express a general idea.

So الجهاز here does not mean one specific device only. It means something like:

• the device
• any device
• whatever device is being used

In natural English, we often say regardless of the device or regardless of what device you use.

So the singular in Arabic is perfectly normal here.

Because ث is a sun letter, while ج is a moon letter.

In الثنائية

The ل of الـ is not pronounced clearly. It assimilates to the next consonant:

• written: الثنائية
• pronounced roughly: ath-thunāʾiyya

In الجهاز

The ل is pronounced normally because ج is a moon letter:

• written: الجهاز
• pronounced roughly: al-jihāz

So:

• الثنائية → ath-th...
• الجهاز → al-j...

This is a very common pronunciation rule in Arabic.

Because in Arabic, the predicate in a nominal sentence is often indefinite.

So:

• المصادقة الثنائية = the definite subject
• مهمة = an indefinite predicate adjective meaning important

This is completely normal Arabic structure.

Compare:

• الكتاب جديد = The book is new
• الجو جميل = The weather is beautiful
• المصادقة الثنائية مهمة = Two-factor authentication is important

So the mismatch is not a mistake; it is standard grammar.

A fully vocalized version would be:

المُصادَقَةُ الثُّنَائِيَّةُ مُهِمَّةٌ بِغَضِّ النَّظَرِ عَنِ الجِهَازِ

The main endings are:

• المصادقةُ → nominative, because it is the subject
• الثنائيةُ → nominative, because it is an adjective matching the subject
• مهمةٌ → nominative, because it is the predicate
• بغضِّ → genitive after بـ
• النظرِ → genitive as part of the expression
• الجهازِ → genitive after عن

In normal everyday writing, these endings are usually not written, but it is useful to know what they would be.

A helpful pronunciation guide is:

al-muṣādaqa ath-thunāʾiyya muhimma, بغضِّ النَّظرِ عنِ الجِهاز

Or more smoothly in connected speech:

al-muṣādaqa ath-thunāʾiyya muhimma bi-ghaḍḍi n-naẓari ʿani l-jihāz

A few sounds to notice:

• ث in الثنائية is like th in think
• غ in بغض is a deep sound, somewhat like a French r
• ض in بغض is a heavy/emphatic d
• ج in الجهاز is j in standard MSA pronunciation

If you want, I can also break the sentence down word by word with transliteration and pronunciation tips.